Asp.Net Deserialize Dictionary<string, object> to an object - c#

What would be the best way to deserialize this
Dictionary<string, object>{
{"fName", "John"},
{"lName", "Doe"},
{"email", "john#doe.net"}
}
to this
class Member{
string fName;
string lName;
string email;
}

NewtonSoft has become so common in ASP.NET applications these days that if I needed a short and sweet solution to this type of mapping I could use some code like this. Sure it might be abusive to introduce a third party library if its not already present, but sometimes we just use what works. And Newtonsoft does!
using Newtonsoft.Json;
class SerializationTests
{
public void DictionarySerializeSample()
{
var dict = new Dictionary<string, object>
{
{"fName", "John"},
{"lName", "Doe"},
{"email", "john#doe.net"}
};
string dictInJson = JsonConvert.SerializeObject(dict);
var member = JsonConvert.DeserializeObject<Member>(dictInJson);
// use Newtonsoft to write out the object re-serialized
Console.WriteLine(JsonConvert.SerializeObject(member, Formatting.Indented));
}
public class Member
{
public string fName;
public string lName;
public string email;
}
}

This isn't really serialization in the normal sense, that usually refers to taking some disk or network formatted data (binary, ASCII, JSON etc) and loading it into a runtime object.
However, if I understand you correctly, I think what you are trying to do is...
public Member( Dictionary<string,object> dictionary )
{
fName = dictionary["fName"];
lName = dictionary["lName"];
email = dictionary["email"];
}
// usage Member m = new Member( inputDictionary );

If the structure is static:
return new Member
{
fName = myDictionary["fName"],
lName = myDictionary["lName"],
email = myDictionary["email"]
};
If the structure is not known at design time:
public static T Hydrate<T>(this Dictionary<string, string> theDictionary,
T myObject = new T()) where T:new() //default/optional parameter is valid in 4.0 only
{
//var myObject = myObject ?? new T(); //alternative in 3.5 and previous
foreach(string key in myDictionary.Keys)
{
var propInfo = typeof(T).GetProperty(key);
if(propInfo == null) throw new ArgumentException("key does not exist");
propInfo.SetValue(myObject, theDictionary[key], null);
}
return myObject;
}

This isn't serialization, it's conversion. If you really want it convertible, then make it convertible. Implement TypeConverter.
Example code
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;
using System.Xml.Linq;
using System.Diagnostics;
using System.Xml.Serialization;
using System.ComponentModel;
using System.Globalization;
namespace ConsoleApplication1
{
internal class MemberConverter : TypeConverter
{
public override bool CanConvertFrom(ITypeDescriptorContext context,
Type sourceType)
{
if (sourceType == typeof(Dictionary<string, object>))
{
return true;
}
return base.CanConvertFrom(context, sourceType);
}
public override object ConvertFrom(ITypeDescriptorContext context,
CultureInfo culture, object value)
{
if (value is Dictionary<string, object>)
{
Member member = new Member();
Dictionary<string, object> d = (Dictionary<string, object>)value;
if (d.ContainsKey("fName")) { member.fName = Convert.ToString(d["fName"]); };
if (d.ContainsKey("lName")) { member.lName = Convert.ToString(d["lName"]); };
if (d.ContainsKey("email")) { member.email = Convert.ToString(d["email"]); };
return member;
}
return base.ConvertFrom(context, culture, value);
}
public override object ConvertTo(ITypeDescriptorContext context,
CultureInfo culture, object value, Type destinationType)
{
if (destinationType == typeof(Dictionary<string, object>))
{
Member member = (Member)value;
Dictionary<string, object> d = new Dictionary<string, object>();
d.Add("fName", member.fName);
d.Add("lName", member.lName);
d.Add("email", member.email);
return d;
}
return base.ConvertTo(context, culture, value, destinationType);
}
}
[TypeConverter(typeof(MemberConverter))]
internal class Member
{
public string fName;
public string lName;
public string email;
}
class Program
{
static void Main(string[] args)
{
var d = new Dictionary<string, object> {
{"fName", "John"},
{"lName", "Doe"},
{"email", "john#doe.net"}
};
Member m = (Member)TypeDescriptor.GetConverter(typeof(Member)).ConvertFrom(d);
Debugger.Break();
}
}
}

One approach that seems to make sense would be to have a static helper function for this.
public static Member Create(Dictionary<string, object inputs)
{
Member oNew = new Member();
oNew.fName = inputs["fName"].ToString();
// etc
return oNew;
}

You could also use reflection to this, it could be a lot of code depending on the objects you're actually using, but it would be a lot more flexible. This probably isn't a complete sample, but it gets you the general idea.
public T InstantiateFromDictionary<T>(Dictionary<string, object> values) where T : new()
{
Type t = typeof(T);
T instance = new T();
foreach(KeyValuePair<string, object> kvp in values)
{
PropertyInfo prop = t.GetProperty(kvp.Key);
prop.SetValue(instance, kvp.Value, null);
}
return instance;
}

Related

cant Mapping Dictionary to Typed object using when object contain enum?

I need to convert Dictionary to object that contain enum but I got error
error : cant cast enum and i cant fix it
private static T DictionaryToObject<T>(IDictionary<string, string> dict) where T : new()
{
var t = new T();
PropertyInfo[] properties = t.GetType().GetProperties();
foreach (PropertyInfo property in properties)
{
if (!dict.Any(x => x.Key.Equals(property.Name, StringComparison.InvariantCultureIgnoreCase)))
continue;
KeyValuePair<string, string> item = dict.First(x => x.Key.Equals(property.Name, StringComparison.InvariantCultureIgnoreCase));
// Find which property type (int, string, double? etc) the CURRENT property is...
Type tPropertyType = t.GetType().GetProperty(property.Name).PropertyType;
// Fix nullables...
Type newT = Nullable.GetUnderlyingType(tPropertyType) ?? tPropertyType;
// ...and change the type
object newA = Convert.ChangeType(item.Value, newT);
t.GetType().GetProperty(property.Name).SetValue(t, newA, null);
}
return t;
}
I think you can convert a dictionary to a typed object by using a simpler way:
a Newtonsoft.Json NuGet package.
namespace MappingTest
{
using System;
using System.Collections.Generic;
using Newtonsoft.Json.Linq;
class Program
{
static void Main(string[] args)
{
var dict = new Dictionary<string, string>
{
{"TestProp1", "TestValue1"},
{"TestProp2", "TestValue2"}
};
var myClass = DictionaryToObject<MyClass>(dict);
Console.WriteLine($"myClass.TestProp1: {myClass.TestProp1}");
Console.WriteLine($"myClass.TestProp2: {myClass.TestProp2}");
}
enum TestValues
{
TestValue1,
TestValue2
}
class MyClass
{
public TestValues? TestProp1 { get; set; }
public TestValues TestProp2 { get; set; }
}
private static T DictionaryToObject<T>(IDictionary<string, string> dict)
{
JObject obj = JObject.FromObject(dict);
return obj.ToObject<T>();
}
}
}

JSON string to C# class object [duplicate]

Is there a way to deserialize JSON content into a C# dynamic type? It would be nice to skip creating a bunch of classes in order to use the DataContractJsonSerializer.
If you are happy to have a dependency upon the System.Web.Helpers assembly, then you can use the Json class:
dynamic data = Json.Decode(json);
It is included with the MVC framework as an additional download to the .NET 4 framework. Be sure to give Vlad an upvote if that's helpful! However if you cannot assume the client environment includes this DLL, then read on.
An alternative deserialisation approach is suggested here. I modified the code slightly to fix a bug and suit my coding style. All you need is this code and a reference to System.Web.Extensions from your project:
using System;
using System.Collections;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Dynamic;
using System.Linq;
using System.Text;
using System.Web.Script.Serialization;
public sealed class DynamicJsonConverter : JavaScriptConverter
{
public override object Deserialize(IDictionary<string, object> dictionary, Type type, JavaScriptSerializer serializer)
{
if (dictionary == null)
throw new ArgumentNullException("dictionary");
return type == typeof(object) ? new DynamicJsonObject(dictionary) : null;
}
public override IDictionary<string, object> Serialize(object obj, JavaScriptSerializer serializer)
{
throw new NotImplementedException();
}
public override IEnumerable<Type> SupportedTypes
{
get { return new ReadOnlyCollection<Type>(new List<Type>(new[] { typeof(object) })); }
}
#region Nested type: DynamicJsonObject
private sealed class DynamicJsonObject : DynamicObject
{
private readonly IDictionary<string, object> _dictionary;
public DynamicJsonObject(IDictionary<string, object> dictionary)
{
if (dictionary == null)
throw new ArgumentNullException("dictionary");
_dictionary = dictionary;
}
public override string ToString()
{
var sb = new StringBuilder("{");
ToString(sb);
return sb.ToString();
}
private void ToString(StringBuilder sb)
{
var firstInDictionary = true;
foreach (var pair in _dictionary)
{
if (!firstInDictionary)
sb.Append(",");
firstInDictionary = false;
var value = pair.Value;
var name = pair.Key;
if (value is string)
{
sb.AppendFormat("{0}:\"{1}\"", name, value);
}
else if (value is IDictionary<string, object>)
{
new DynamicJsonObject((IDictionary<string, object>)value).ToString(sb);
}
else if (value is ArrayList)
{
sb.Append(name + ":[");
var firstInArray = true;
foreach (var arrayValue in (ArrayList)value)
{
if (!firstInArray)
sb.Append(",");
firstInArray = false;
if (arrayValue is IDictionary<string, object>)
new DynamicJsonObject((IDictionary<string, object>)arrayValue).ToString(sb);
else if (arrayValue is string)
sb.AppendFormat("\"{0}\"", arrayValue);
else
sb.AppendFormat("{0}", arrayValue);
}
sb.Append("]");
}
else
{
sb.AppendFormat("{0}:{1}", name, value);
}
}
sb.Append("}");
}
public override bool TryGetMember(GetMemberBinder binder, out object result)
{
if (!_dictionary.TryGetValue(binder.Name, out result))
{
// return null to avoid exception. caller can check for null this way...
result = null;
return true;
}
result = WrapResultObject(result);
return true;
}
public override bool TryGetIndex(GetIndexBinder binder, object[] indexes, out object result)
{
if (indexes.Length == 1 && indexes[0] != null)
{
if (!_dictionary.TryGetValue(indexes[0].ToString(), out result))
{
// return null to avoid exception. caller can check for null this way...
result = null;
return true;
}
result = WrapResultObject(result);
return true;
}
return base.TryGetIndex(binder, indexes, out result);
}
private static object WrapResultObject(object result)
{
var dictionary = result as IDictionary<string, object>;
if (dictionary != null)
return new DynamicJsonObject(dictionary);
var arrayList = result as ArrayList;
if (arrayList != null && arrayList.Count > 0)
{
return arrayList[0] is IDictionary<string, object>
? new List<object>(arrayList.Cast<IDictionary<string, object>>().Select(x => new DynamicJsonObject(x)))
: new List<object>(arrayList.Cast<object>());
}
return result;
}
}
#endregion
}
You can use it like this:
string json = ...;
var serializer = new JavaScriptSerializer();
serializer.RegisterConverters(new[] { new DynamicJsonConverter() });
dynamic obj = serializer.Deserialize(json, typeof(object));
So, given a JSON string:
{
"Items":[
{ "Name":"Apple", "Price":12.3 },
{ "Name":"Grape", "Price":3.21 }
],
"Date":"21/11/2010"
}
The following code will work at runtime:
dynamic data = serializer.Deserialize(json, typeof(object));
data.Date; // "21/11/2010"
data.Items.Count; // 2
data.Items[0].Name; // "Apple"
data.Items[0].Price; // 12.3 (as a decimal)
data.Items[1].Name; // "Grape"
data.Items[1].Price; // 3.21 (as a decimal)
It's pretty simple using Json.NET:
dynamic stuff = JsonConvert.DeserializeObject("{ 'Name': 'Jon Smith', 'Address': { 'City': 'New York', 'State': 'NY' }, 'Age': 42 }");
string name = stuff.Name;
string address = stuff.Address.City;
Also using Newtonsoft.Json.Linq:
dynamic stuff = JObject.Parse("{ 'Name': 'Jon Smith', 'Address': { 'City': 'New York', 'State': 'NY' }, 'Age': 42 }");
string name = stuff.Name;
string address = stuff.Address.City;
Documentation: Querying JSON with dynamic
You can do this using System.Web.Helpers.Json - its Decode method returns a dynamic object which you can traverse as you like.
It's included in the System.Web.Helpers assembly (.NET 4.0).
var dynamicObject = Json.Decode(jsonString);
.NET 4.0 has a built-in library to do this:
using System.Web.Script.Serialization;
JavaScriptSerializer jss = new JavaScriptSerializer();
var d = jss.Deserialize<dynamic>(str);
This is the simplest way.
Simple "string JSON data" to object without any third-party DLL file:
WebClient client = new WebClient();
string getString = client.DownloadString("https://graph.facebook.com/zuck");
JavaScriptSerializer serializer = new JavaScriptSerializer();
dynamic item = serializer.Deserialize<object>(getString);
string name = item["name"];
//note: JavaScriptSerializer in this namespaces
//System.Web.Script.Serialization.JavaScriptSerializer
Note: You can also using your custom object.
Personel item = serializer.Deserialize<Personel>(getString);
You can achieve that with the help of Newtonsoft.Json. Install it from NuGet and then:
using Newtonsoft.Json;
dynamic results = JsonConvert.DeserializeObject<dynamic>(YOUR_JSON);
JsonFx can deserialize JSON content into dynamic objects.
Serialize to/from dynamic types (default for .NET 4.0):
var reader = new JsonReader(); var writer = new JsonWriter();
string input = #"{ ""foo"": true, ""array"": [ 42, false, ""Hello!"", null ] }";
dynamic output = reader.Read(input);
Console.WriteLine(output.array[0]); // 42
string json = writer.Write(output);
Console.WriteLine(json); // {"foo":true,"array":[42,false,"Hello!",null]}
Another way using Newtonsoft.Json:
dynamic stuff = Newtonsoft.Json.JsonConvert.DeserializeObject("{ color: 'red', value: 5 }");
string color = stuff.color;
int value = stuff.value;
I came here to find an answer for .NET Core, without any third-party or additional references. It works fine if you use ExpandoObject with the standard JsonSerializer class. Here is the example that worked for me:
using System.Text.Json;
using System.Dynamic;
dynamic json = JsonSerializer.Deserialize<ExpandoObject>(jsonText);
Console.WriteLine(json.name);
This code prints out the string value of a name property that exists within the JSON text passed into the Deserialize method. Voila - no additional libraries, no nothing. Just .NET core.
Edit: May have a problem for several levels of json with nested elements. Worked for a single-level flat object.
I made a new version of the DynamicJsonConverter that uses Expando Objects. I used expando objects, because I wanted to Serialize the dynamic back into JSON using Json.NET.
using System;
using System.Collections;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Dynamic;
using System.Web.Script.Serialization;
public static class DynamicJson
{
public static dynamic Parse(string json)
{
JavaScriptSerializer jss = new JavaScriptSerializer();
jss.RegisterConverters(new JavaScriptConverter[] { new DynamicJsonConverter() });
dynamic glossaryEntry = jss.Deserialize(json, typeof(object)) as dynamic;
return glossaryEntry;
}
class DynamicJsonConverter : JavaScriptConverter
{
public override object Deserialize(IDictionary<string, object> dictionary, Type type, JavaScriptSerializer serializer)
{
if (dictionary == null)
throw new ArgumentNullException("dictionary");
var result = ToExpando(dictionary);
return type == typeof(object) ? result : null;
}
private static ExpandoObject ToExpando(IDictionary<string, object> dictionary)
{
var result = new ExpandoObject();
var dic = result as IDictionary<String, object>;
foreach (var item in dictionary)
{
var valueAsDic = item.Value as IDictionary<string, object>;
if (valueAsDic != null)
{
dic.Add(item.Key, ToExpando(valueAsDic));
continue;
}
var arrayList = item.Value as ArrayList;
if (arrayList != null && arrayList.Count > 0)
{
dic.Add(item.Key, ToExpando(arrayList));
continue;
}
dic.Add(item.Key, item.Value);
}
return result;
}
private static ArrayList ToExpando(ArrayList obj)
{
ArrayList result = new ArrayList();
foreach (var item in obj)
{
var valueAsDic = item as IDictionary<string, object>;
if (valueAsDic != null)
{
result.Add(ToExpando(valueAsDic));
continue;
}
var arrayList = item as ArrayList;
if (arrayList != null && arrayList.Count > 0)
{
result.Add(ToExpando(arrayList));
continue;
}
result.Add(item);
}
return result;
}
public override IDictionary<string, object> Serialize(object obj, JavaScriptSerializer serializer)
{
throw new NotImplementedException();
}
public override IEnumerable<Type> SupportedTypes
{
get { return new ReadOnlyCollection<Type>(new List<Type>(new[] { typeof(object) })); }
}
}
}
Creating dynamic objects with Newtonsoft.Json works really great.
//json is your string containing the JSON value
dynamic data = JsonConvert.DeserializeObject<dynamic>(json);
Now you can access the data object just like if it was a regular object. This is the JSON object we currently have as an example:
{ "ID":123,"Name":"Jack","Numbers":[1, 2, 3] }
This is how you access it after deserialization:
data.ID //Retrieve the int
data.Name //Retrieve the string
data.Numbers[0] //Retrieve the first element in the array
I use http://json2csharp.com/ to get a class representing the JSON object.
Input:
{
"name":"John",
"age":31,
"city":"New York",
"Childs":[
{
"name":"Jim",
"age":11
},
{
"name":"Tim",
"age":9
}
]
}
Output:
public class Child
{
public string name { get; set; }
public int age { get; set; }
}
public class Person
{
public string name { get; set; }
public int age { get; set; }
public string city { get; set; }
public List<Child> Childs { get; set; }
}
After that I use Newtonsoft.Json to fill the class:
using Newtonsoft.Json;
namespace GitRepositoryCreator.Common
{
class JObjects
{
public static string Get(object p_object)
{
return JsonConvert.SerializeObject(p_object);
}
internal static T Get<T>(string p_object)
{
return JsonConvert.DeserializeObject<T>(p_object);
}
}
}
You can call it like this:
Person jsonClass = JObjects.Get<Person>(stringJson);
string stringJson = JObjects.Get(jsonClass);
PS:
If your JSON variable name is not a valid C# name (name starts with $) you can fix that like this:
public class Exception
{
[JsonProperty(PropertyName = "$id")]
public string id { get; set; }
public object innerException { get; set; }
public string message { get; set; }
public string typeName { get; set; }
public string typeKey { get; set; }
public int errorCode { get; set; }
public int eventId { get; set; }
}
The simplest way is:
Just include this DLL file.
Use the code like this:
dynamic json = new JDynamic("{a:'abc'}");
// json.a is a string "abc"
dynamic json = new JDynamic("{a:3.1416}");
// json.a is 3.1416m
dynamic json = new JDynamic("{a:1}");
// json.a is
dynamic json = new JDynamic("[1,2,3]");
/json.Length/json.Count is 3
// And you can use json[0]/ json[2] to get the elements
dynamic json = new JDynamic("{a:[1,2,3]}");
//json.a.Length /json.a.Count is 3.
// And you can use json.a[0]/ json.a[2] to get the elements
dynamic json = new JDynamic("[{b:1},{c:1}]");
// json.Length/json.Count is 2.
// And you can use the json[0].b/json[1].c to get the num.
Another option is to "Paste JSON as classes" so it can be deserialised quick and easy.
Simply copy your entire JSON
In Visual Studio: Click Edit → Paste Special → Paste JSON as classes
Here is a better explanation n piccas... ‘Paste JSON As Classes’ in ASP.NET and Web Tools 2012.2 RC
You can extend the JavaScriptSerializer to recursively copy the dictionary it created to expando object(s) and then use them dynamically:
static class JavaScriptSerializerExtensions
{
public static dynamic DeserializeDynamic(this JavaScriptSerializer serializer, string value)
{
var dictionary = serializer.Deserialize<IDictionary<string, object>>(value);
return GetExpando(dictionary);
}
private static ExpandoObject GetExpando(IDictionary<string, object> dictionary)
{
var expando = (IDictionary<string, object>)new ExpandoObject();
foreach (var item in dictionary)
{
var innerDictionary = item.Value as IDictionary<string, object>;
if (innerDictionary != null)
{
expando.Add(item.Key, GetExpando(innerDictionary));
}
else
{
expando.Add(item.Key, item.Value);
}
}
return (ExpandoObject)expando;
}
}
Then you just need to having a using statement for the namespace you defined the extension in (consider just defining them in System.Web.Script.Serialization... another trick is to not use a namespace, then you don't need the using statement at all) and you can consume them like so:
var serializer = new JavaScriptSerializer();
var value = serializer.DeserializeDynamic("{ 'Name': 'Jon Smith', 'Address': { 'City': 'New York', 'State': 'NY' }, 'Age': 42 }");
var name = (string)value.Name; // Jon Smith
var age = (int)value.Age; // 42
var address = value.Address;
var city = (string)address.City; // New York
var state = (string)address.State; // NY
You can use using Newtonsoft.Json
var jRoot =
JsonConvert.DeserializeObject<dynamic>(Encoding.UTF8.GetString(resolvedEvent.Event.Data));
resolvedEvent.Event.Data is my response getting from calling core Event .
Try this:
var units = new { Name = "Phone", Color= "White" };
var jsonResponse = JsonConvert.DeserializeAnonymousType(json, units);
I am using like this in my code and it's working fine
using System.Web.Script.Serialization;
JavaScriptSerializer oJS = new JavaScriptSerializer();
RootObject oRootObject = new RootObject();
oRootObject = oJS.Deserialize<RootObject>(Your JSon String);
Look at the article I wrote on CodeProject, one that answers the question precisely:
Dynamic types with JSON.NET
There is way too much for re-posting it all here, and even less point since that article has an attachment with the key/required source file.
For that I would use JSON.NET to do the low-level parsing of the JSON stream and then build up the object hierarchy out of instances of the ExpandoObject class.
To get an ExpandoObject:
using Newtonsoft.Json;
using Newtonsoft.Json.Converters;
Container container = JsonConvert.Deserialize<Container>(jsonAsString, new ExpandoObjectConverter());
Deserializing in JSON.NET can be dynamic using the JObject class, which is included in that library. My JSON string represents these classes:
public class Foo {
public int Age {get;set;}
public Bar Bar {get;set;}
}
public class Bar {
public DateTime BDay {get;set;}
}
Now we deserialize the string WITHOUT referencing the above classes:
var dyn = JsonConvert.DeserializeObject<JObject>(jsonAsFooString);
JProperty propAge = dyn.Properties().FirstOrDefault(i=>i.Name == "Age");
if(propAge != null) {
int age = int.Parse(propAge.Value.ToString());
Console.WriteLine("age=" + age);
}
//or as a one-liner:
int myage = int.Parse(dyn.Properties().First(i=>i.Name == "Age").Value.ToString());
Or if you want to go deeper:
var propBar = dyn.Properties().FirstOrDefault(i=>i.Name == "Bar");
if(propBar != null) {
JObject o = (JObject)propBar.First();
var propBDay = o.Properties().FirstOrDefault (i => i.Name=="BDay");
if(propBDay != null) {
DateTime bday = DateTime.Parse(propBDay.Value.ToString());
Console.WriteLine("birthday=" + bday.ToString("MM/dd/yyyy"));
}
}
//or as a one-liner:
DateTime mybday = DateTime.Parse(((JObject)dyn.Properties().First(i=>i.Name == "Bar").First()).Properties().First(i=>i.Name == "BDay").Value.ToString());
See post for a complete example.
The object you want DynamicJSONObject is included in the System.Web.Helpers.dll from the ASP.NET Web Pages package, which is part of WebMatrix.
There is a lightweight JSON library for C# called SimpleJson.
It supports .NET 3.5+, Silverlight and Windows Phone 7.
It supports dynamic for .NET 4.0
It can also be installed as a NuGet package
Install-Package SimpleJson
Use DataSet(C#) with JavaScript. A simple function for creating a JSON stream with DataSet input. Create JSON content like (multi table dataset):
[[{a:1,b:2,c:3},{a:3,b:5,c:6}],[{a:23,b:45,c:35},{a:58,b:59,c:45}]]
Just client side, use eval. For example,
var d = eval('[[{a:1,b:2,c:3},{a:3,b:5,c:6}],[{a:23,b:45,c:35},{a:58,b:59,c:45}]]')
Then use:
d[0][0].a // out 1 from table 0 row 0
d[1][1].b // out 59 from table 1 row 1
// Created by Behnam Mohammadi And Saeed Ahmadian
public string jsonMini(DataSet ds)
{
int t = 0, r = 0, c = 0;
string stream = "[";
for (t = 0; t < ds.Tables.Count; t++)
{
stream += "[";
for (r = 0; r < ds.Tables[t].Rows.Count; r++)
{
stream += "{";
for (c = 0; c < ds.Tables[t].Columns.Count; c++)
{
stream += ds.Tables[t].Columns[c].ToString() + ":'" +
ds.Tables[t].Rows[r][c].ToString() + "',";
}
if (c>0)
stream = stream.Substring(0, stream.Length - 1);
stream += "},";
}
if (r>0)
stream = stream.Substring(0, stream.Length - 1);
stream += "],";
}
if (t>0)
stream = stream.Substring(0, stream.Length - 1);
stream += "];";
return stream;
}
How to parse easy JSON content with dynamic & JavaScriptSerializer
Please add reference of System.Web.Extensions and add this namespace using System.Web.Script.Serialization; at top:
public static void EasyJson()
{
var jsonText = #"{
""some_number"": 108.541,
""date_time"": ""2011-04-13T15:34:09Z"",
""serial_number"": ""SN1234""
}";
var jss = new JavaScriptSerializer();
var dict = jss.Deserialize<dynamic>(jsonText);
Console.WriteLine(dict["some_number"]);
Console.ReadLine();
}
How to parse nested & complex json with dynamic & JavaScriptSerializer
Please add reference of System.Web.Extensions and add this namespace using System.Web.Script.Serialization; at top:
public static void ComplexJson()
{
var jsonText = #"{
""some_number"": 108.541,
""date_time"": ""2011-04-13T15:34:09Z"",
""serial_number"": ""SN1234"",
""more_data"": {
""field1"": 1.0,
""field2"": ""hello""
}
}";
var jss = new JavaScriptSerializer();
var dict = jss.Deserialize<dynamic>(jsonText);
Console.WriteLine(dict["some_number"]);
Console.WriteLine(dict["more_data"]["field2"]);
Console.ReadLine();
}
I want to do this programmatically in unit tests, I do have the luxury of typing it out.
My solution is:
var dict = JsonConvert.DeserializeObject<ExpandoObject>(json) as IDictionary<string, object>;
Now I can assert that
dict.ContainsKey("ExpectedProperty");
With Cinchoo ETL - an open source library available to parse JSON into a dynamic object:
string json = #"{
""key1"": [
{
""action"": ""open"",
""timestamp"": ""2018-09-05 20:46:00"",
""url"": null,
""ip"": ""66.102.6.98""
}
]
}";
using (var p = ChoJSONReader.LoadText(json)
.WithJSONPath("$..key1")
)
{
foreach (var rec in p)
{
Console.WriteLine("Action: " + rec.action);
Console.WriteLine("Timestamp: " + rec.timestamp);
Console.WriteLine("URL: " + rec.url);
Console.WriteLine("IP address: " + rec.ip);
}
}
Output:
Action: open
Timestamp: 2018-09-05 20:46:00
URL: http://www.google.com
IP address: 66.102.6.98
Sample fiddle: https://dotnetfiddle.net/S0ehSV
For more information, please visit codeproject articles
Disclaimer: I'm the author of this library.
try this way!
JSON example:
[{
"id": 140,
"group": 1,
"text": "xxx",
"creation_date": 123456,
"created_by": "xxx#gmail.co",
"tags": ["xxxxx"]
}, {
"id": 141,
"group": 1,
"text": "xxxx",
"creation_date": 123456,
"created_by": "xxx#gmail.com",
"tags": ["xxxxx"]
}]
C# code:
var jsonString = (File.ReadAllText(Path.Combine(Directory.GetCurrentDirectory(),"delete_result.json")));
var objects = JsonConvert.DeserializeObject<dynamic>(jsonString);
foreach(var o in objects)
{
Console.WriteLine($"{o.id.ToString()}");
}
I really like System.Web.Helpers,
dynamic data = Json.Decode(json);
as it supports usage like
var val = data.Members.NumberTen;
or
var val data.Members["10"];
The reference to System.Web.Helpers.DLL is really crazy, it is not even console and desktop app friendly. Here is my attempt to extract the same functionalities as a standalone file directly from https://github.com/mono/aspnetwebstack/tree/master/src/System.Web.Helpers
(Share this as for education purpose only)
// Copyright (c) Microsoft Open Technologies, Inc. All rights reserved. See License.txt in the project root for license information.
using System.Collections.Generic;
using System.Diagnostics;
using System.Diagnostics.CodeAnalysis;
using System.Dynamic;
using System.Linq.Expressions;
using System.Runtime.CompilerServices;
using Microsoft.CSharp.RuntimeBinder;
using System.Web.Script.Serialization;
using System.IO;
using System.Collections;
using System.Linq;
using System.Globalization;
namespace System.Web.Helpers
{
public static class Json
{
private static readonly JavaScriptSerializer _serializer = CreateSerializer();
public static string Encode(object value)
{
// Serialize our dynamic array type as an array
DynamicJsonArray jsonArray = value as DynamicJsonArray;
if (jsonArray != null)
{
return _serializer.Serialize((object[])jsonArray);
}
return _serializer.Serialize(value);
}
public static void Write(object value, TextWriter writer)
{
writer.Write(_serializer.Serialize(value));
}
public static dynamic Decode(string value)
{
return WrapObject(_serializer.DeserializeObject(value));
}
public static dynamic Decode(string value, Type targetType)
{
return WrapObject(_serializer.Deserialize(value, targetType));
}
public static T Decode<T>(string value)
{
return _serializer.Deserialize<T>(value);
}
private static JavaScriptSerializer CreateSerializer()
{
JavaScriptSerializer serializer = new JavaScriptSerializer();
serializer.RegisterConverters(new[] { new DynamicJavaScriptConverter() });
return serializer;
}
internal class DynamicJavaScriptConverter : JavaScriptConverter
{
public override IEnumerable<Type> SupportedTypes
{
get
{
yield return typeof(IDynamicMetaObjectProvider);
yield return typeof(DynamicObject);
}
}
public override object Deserialize(IDictionary<string, object> dictionary, Type type, JavaScriptSerializer serializer)
{
throw new NotSupportedException();
}
public override IDictionary<string, object> Serialize(object obj, JavaScriptSerializer serializer)
{
Dictionary<string, object> dictionary = new Dictionary<string, object>(StringComparer.OrdinalIgnoreCase);
IEnumerable<string> memberNames = DynamicHelper.GetMemberNames(obj);
foreach (string item in memberNames)
{
dictionary[item] = DynamicHelper.GetMemberValue(obj, item);
}
return dictionary;
}
}
internal static dynamic WrapObject(object value)
{
// The JavaScriptSerializer returns IDictionary<string, object> for objects
// and object[] for arrays, so we wrap those in different dynamic objects
// so we can access the object graph using dynamic
var dictionaryValues = value as IDictionary<string, object>;
if (dictionaryValues != null)
{
return new DynamicJsonObject(dictionaryValues);
}
var arrayValues = value as object[];
if (arrayValues != null)
{
return new DynamicJsonArray(arrayValues);
}
return value;
}
}
// REVIEW: Consider implementing ICustomTypeDescriptor and IDictionary<string, object>
public class DynamicJsonObject : DynamicObject
{
private readonly IDictionary<string, object> _values;
public DynamicJsonObject(IDictionary<string, object> values)
{
Debug.Assert(values != null);
_values = values.ToDictionary(p => p.Key, p => Json.WrapObject(p.Value),
StringComparer.OrdinalIgnoreCase);
}
public override bool TryConvert(ConvertBinder binder, out object result)
{
result = null;
if (binder.Type.IsAssignableFrom(_values.GetType()))
{
result = _values;
}
else
{
throw new InvalidOperationException(String.Format(CultureInfo.CurrentCulture, "HelpersResources.Json_UnableToConvertType", binder.Type));
}
return true;
}
public override bool TryGetMember(GetMemberBinder binder, out object result)
{
result = GetValue(binder.Name);
return true;
}
public override bool TrySetMember(SetMemberBinder binder, object value)
{
_values[binder.Name] = Json.WrapObject(value);
return true;
}
public override bool TrySetIndex(SetIndexBinder binder, object[] indexes, object value)
{
string key = GetKey(indexes);
if (!String.IsNullOrEmpty(key))
{
_values[key] = Json.WrapObject(value);
}
return true;
}
public override bool TryGetIndex(GetIndexBinder binder, object[] indexes, out object result)
{
string key = GetKey(indexes);
result = null;
if (!String.IsNullOrEmpty(key))
{
result = GetValue(key);
}
return true;
}
private static string GetKey(object[] indexes)
{
if (indexes.Length == 1)
{
return (string)indexes[0];
}
// REVIEW: Should this throw?
return null;
}
public override IEnumerable<string> GetDynamicMemberNames()
{
return _values.Keys;
}
private object GetValue(string name)
{
object result;
if (_values.TryGetValue(name, out result))
{
return result;
}
return null;
}
}
[SuppressMessage("Microsoft.Naming", "CA1710:IdentifiersShouldHaveCorrectSuffix", Justification = "This class isn't meant to be used directly")]
public class DynamicJsonArray : DynamicObject, IEnumerable<object>
{
private readonly object[] _arrayValues;
public DynamicJsonArray(object[] arrayValues)
{
Debug.Assert(arrayValues != null);
_arrayValues = arrayValues.Select(Json.WrapObject).ToArray();
}
public int Length
{
get { return _arrayValues.Length; }
}
public dynamic this[int index]
{
get { return _arrayValues[index]; }
set { _arrayValues[index] = Json.WrapObject(value); }
}
public override bool TryConvert(ConvertBinder binder, out object result)
{
if (_arrayValues.GetType().IsAssignableFrom(binder.Type))
{
result = _arrayValues;
return true;
}
return base.TryConvert(binder, out result);
}
public override bool TryGetMember(GetMemberBinder binder, out object result)
{
// Testing for members should never throw. This is important when dealing with
// services that return different json results. Testing for a member shouldn't throw,
// it should just return null (or undefined)
result = null;
return true;
}
public IEnumerator GetEnumerator()
{
return _arrayValues.GetEnumerator();
}
private IEnumerable<object> GetEnumerable()
{
return _arrayValues.AsEnumerable();
}
IEnumerator<object> IEnumerable<object>.GetEnumerator()
{
return GetEnumerable().GetEnumerator();
}
[SuppressMessage("Microsoft.Usage", "CA2225:OperatorOverloadsHaveNamedAlternates", Justification = "This class isn't meant to be used directly")]
public static implicit operator object[](DynamicJsonArray obj)
{
return obj._arrayValues;
}
[SuppressMessage("Microsoft.Usage", "CA2225:OperatorOverloadsHaveNamedAlternates", Justification = "This class isn't meant to be used directly")]
public static implicit operator Array(DynamicJsonArray obj)
{
return obj._arrayValues;
}
}
/// <summary>
/// Helper to evaluate different method on dynamic objects
/// </summary>
public static class DynamicHelper
{
// We must pass in "object" instead of "dynamic" for the target dynamic object because if we use dynamic, the compiler will
// convert the call to this helper into a dynamic expression, even though we don't need it to be. Since this class is internal,
// it cannot be accessed from a dynamic expression and thus we get errors.
// Dev10 Bug 914027 - Changed the first parameter from dynamic to object, see comment at top for details
public static bool TryGetMemberValue(object obj, string memberName, out object result)
{
try
{
result = GetMemberValue(obj, memberName);
return true;
}
catch (RuntimeBinderException)
{
}
catch (RuntimeBinderInternalCompilerException)
{
}
// We catch the C# specific runtime binder exceptions since we're using the C# binder in this case
result = null;
return false;
}
// Dev10 Bug 914027 - Changed the first parameter from dynamic to object, see comment at top for details
[SuppressMessage("Microsoft.Design", "CA1031:DoNotCatchGeneralExceptionTypes", Justification = "We want to swallow exceptions that happen during runtime binding")]
public static bool TryGetMemberValue(object obj, GetMemberBinder binder, out object result)
{
try
{
// VB us an instance of GetBinderAdapter that does not implement FallbackGetMemeber. This causes lookup of property expressions on dynamic objects to fail.
// Since all types are private to the assembly, we assume that as long as they belong to CSharp runtime, it is the right one.
if (typeof(Binder).Assembly.Equals(binder.GetType().Assembly))
{
// Only use the binder if its a C# binder.
result = GetMemberValue(obj, binder);
}
else
{
result = GetMemberValue(obj, binder.Name);
}
return true;
}
catch
{
result = null;
return false;
}
}
// Dev10 Bug 914027 - Changed the first parameter from dynamic to object, see comment at top for details
public static object GetMemberValue(object obj, string memberName)
{
var callSite = GetMemberAccessCallSite(memberName);
return callSite.Target(callSite, obj);
}
// Dev10 Bug 914027 - Changed the first parameter from dynamic to object, see comment at top for details
public static object GetMemberValue(object obj, GetMemberBinder binder)
{
var callSite = GetMemberAccessCallSite(binder);
return callSite.Target(callSite, obj);
}
// dynamic d = new object();
// object s = d.Name;
// The following code gets generated for this expression:
// callSite = CallSite<Func<CallSite, object, object>>.Create(Binder.GetMember(CSharpBinderFlags.None, "Name", typeof(Program), new CSharpArgumentInfo[] { CSharpArgumentInfo.Create(CSharpArgumentInfoFlags.None, null) }));
// callSite.Target(callSite, d);
// typeof(Program) is the containing type of the dynamic operation.
// Dev10 Bug 914027 - Changed the callsite's target parameter from dynamic to object, see comment at top for details
public static CallSite<Func<CallSite, object, object>> GetMemberAccessCallSite(string memberName)
{
var binder = Binder.GetMember(CSharpBinderFlags.None, memberName, typeof(DynamicHelper), new[] { CSharpArgumentInfo.Create(CSharpArgumentInfoFlags.None, null) });
return GetMemberAccessCallSite(binder);
}
// Dev10 Bug 914027 - Changed the callsite's target parameter from dynamic to object, see comment at top for details
public static CallSite<Func<CallSite, object, object>> GetMemberAccessCallSite(CallSiteBinder binder)
{
return CallSite<Func<CallSite, object, object>>.Create(binder);
}
// Dev10 Bug 914027 - Changed the first parameter from dynamic to object, see comment at top for details
public static IEnumerable<string> GetMemberNames(object obj)
{
var provider = obj as IDynamicMetaObjectProvider;
Debug.Assert(provider != null, "obj doesn't implement IDynamicMetaObjectProvider");
Expression parameter = Expression.Parameter(typeof(object));
return provider.GetMetaObject(parameter).GetDynamicMemberNames();
}
}
}

Figure out which properties accessed on expando object

I use a template engine that renders templates from c# objects (nested). I would like to reflect and figure out which properties / objects are used in each template string.
An ideal way would be to build a "dummy" object representing the right shape and render this in the template. I would then inspect this object afterwards to find out which properties were accessed. This would allow me to keep this logic independant of the template library.
Any idea how i might implement this? The expando object is built dynamically like this:
var dynamicObject = new ExpandoObject() as IDictionary<string, Object>;
foreach (var property in properties) {
dynamicObject.Add(property.Key,property.Value);
}
Had some ideas along these lines:
public class DummyObject {
public DummyObject() {
Accessed = new Dictionary<string, bool>();
}
public Dictionary<string, bool> Accessed;
object MyProp {
get {
Accessed["MyProp"] = true;
return "";
}
}
}
But this custom property obviously doesn't work with the dictionary / expando object. Any ideas of a route forward here?
You can override the TryGetMember method on DynamicObject:
public sealed class LoggedPropertyAccess : DynamicObject {
public readonly HashSet<string> accessedPropertyNames = new HashSet<string>();
public override bool TryGetMember(GetMemberBinder binder, out object result) {
accessedPropertyNames.Add(binder.Name);
result = "";
return true;
}
}
and then the following will output the accessed property names
dynamic testObject = new LoggedPropertyAccess();
string firstname = testObject.FirstName;
string lastname = testObject.LastName;
foreach (var propertyName in testObject.accessedPropertyNames) {
Console.WriteLine(propertyName);
}
Console.ReadKey();
N.B. There is still an issue here -- this works only as long as the template library expects only strings from the properties. The following code will fail, because every property will return a string:
DateTime dob = testObject.DOB;
In order to resolve this, and also allow for nested objects, have TryGetMember return a new instance of LoggedPropertyAccess. Then, you can override the TryConvert method as well; where you can return different values based on the conversion to different types (complete code):
using System;
using System.Collections.Generic;
using System.Dynamic;
namespace DynamicObjectGetterOverride {
public sealed class LoggedPropertyAccess : DynamicObject {
public readonly Dictionary<string, object> __Properties = new Dictionary<string, object>();
public readonly HashSet<string> __AccessedProperties = new HashSet<string>();
public override bool TryGetMember(GetMemberBinder binder, out object result) {
if (!__Properties.TryGetValue(binder.Name, out result)) {
var ret = new LoggedPropertyAccess();
__Properties[binder.Name] = ret;
result = ret;
}
__AccessedProperties.Add(binder.Name);
return true;
}
//this allows for setting values which aren't instances of LoggedPropertyAccess
public override bool TrySetMember(SetMemberBinder binder, object value) {
__Properties[binder.Name] = value;
return true;
}
private static Dictionary<Type, Func<object>> typeActions = new Dictionary<Type, Func<object>>() {
{typeof(string), () => "dummy string" },
{typeof(int), () => 42 },
{typeof(DateTime), () => DateTime.Today }
};
public override bool TryConvert(ConvertBinder binder, out object result) {
if (typeActions.TryGetValue(binder.Type, out var action)) {
result = action();
return true;
}
return base.TryConvert(binder, out result);
}
}
}
and use as follows:
using System;
using static System.Console;
namespace DynamicObjectGetterOverride {
class Program {
static void Main(string[] args) {
dynamic testObject = new LoggedPropertyAccess();
DateTime dob = testObject.DOB;
string firstname = testObject.FirstName;
string lastname = testObject.LastName;
dynamic address = testObject.Address;
address.House = "123";
address.Street = "AnyStreet";
address.City = "Anytown";
address.State = "ST";
address.Country = "USA";
WriteLine("----- Writes the returned values from reading the properties");
WriteLine(new { firstname, lastname, dob });
WriteLine();
WriteLine("----- Writes the actual values of each property");
foreach (var kvp in testObject.__Properties) {
WriteLine($"{kvp.Key} = {kvp.Value}");
}
WriteLine();
WriteLine("----- Writes the actual values of a nested object");
foreach (var kvp in testObject.Address.__Properties) {
WriteLine($"{kvp.Key} = {kvp.Value}");
}
WriteLine();
WriteLine("----- Writes the names of the accessed properties");
foreach (var propertyName in testObject.__AccessedProperties) {
WriteLine(propertyName);
}
ReadKey();
}
}
}

Generate dynamic object from dictionary with C # Reflection

I've been researching a bit about reflections in C # and would like to know if I use a dictionary with keys-values ​​can create an object with the variable with the name of each key in the dictionary and their values​​, the key value of that dictionary.
I have a method that does the opposite, that extracts an object from a dictionary, this dictionary contains the keys and the class properties and their values​​, the value of the properties.
I wonder how to do this if possible.
Below is my method, which extracts a dictionary of an object:
protected Dictionary<String, String> getObjectProperty(object objeto)
{
Dictionary<String, String> dictionary = new Dictionary<String, String>();
Type type = objeto.GetType();
FieldInfo[] field = type.GetFields();
PropertyInfo[] myPropertyInfo = type.GetProperties();
String value = null;
foreach (var propertyInfo in myPropertyInfo)
{
if (propertyInfo.GetIndexParameters().Length == 0)
{
value = (string)propertyInfo.GetValue(objeto, null);
value = value == null ? null : value;
dictionary.Add(propertyInfo.Name.ToString(), value);
}
}
return dictionary;
}
If you've already got a dictionary, I'd avoid reflection and just use DynamicObject
For example:
public class DynamicDictionary : DynamicObject
{
private readonly Dictionary<string, object> dictionary;
public DynamicDictionary(Dictionary<string, object> dictionary)
{
this.dictionary = dictionary;
}
public override bool TryGetMember(
GetMemberBinder binder, out object result)
{
return dictionary.TryGetValue(binder.Name, out result);
}
public override bool TrySetMember(
SetMemberBinder binder, object value)
{
dictionary[binder.Name] = value;
return true;
}
}
Which can be used as follows:
dynamic x = new DynamicDictionary(
new Dictionary<string, object> {{"Name", "Peter"}});
Console.WriteLine(x.Name);
I am not sure if this is what you're looking for, but judging by your question, I think you want to
instantiate types at run time from the types located in a dictionary, which will be obtained by providing a key.
If that is so, then you can create the following class which will hold key-value pairs of strings which will be your keys, and Types which will represent your values which will be instantiated.
class DictionaryActivator
{
Dictionary<string, Type> Dictionary = new Dictionary<string, Type>();
public DictionaryActivator()
{
Dictionary.Add("MyCar", typeof(Car));
Dictionary.Add("MyHouse", typeof(House));
Dictionary.Add("MyFruit", typeof(Fruit));
Dictionary.Add("MyComputer", typeof(Computer));
}
public T GetInstance<T>(string type, params object[] parameters)
{
if (parameters.Count() == 0)
{
return (T)Activator.CreateInstance(Dictionary[type]);
}
else
{
return (T)Activator.CreateInstance(Dictionary[type], parameters.ToArray());
}
}
}
You can also create four test classes to test this setup.
class House
{
public int Number = 25;
}
class Car
{
public double Price = 50000;
}
class Fruit
{
public string Name = "Apple";
}
class Computer
{
public string Cpu { get; set; }
public string Gpu { get; set; }
public Computer(string cpu, string gpu)
{
Cpu = cpu;
Gpu = gpu;
}
}
Once this is done, you can run the following lines of code to get all the types from the dictionary, instantiate them and cast them to appropriate types. As you might notice, the last Computer example is showing you how to add multiple parameters (in this case two) to the newly created instance and return it as an instance of type object.
In the end you can cast it to the Computer type so you can check that the constructor parameters actually went to the corresponding properties.
class Program
{
static void Main()
{
var source = new DictionaryActivator();
Console.WriteLine(source.GetInstance<Car>("MyCar").Price);
Console.WriteLine(source.GetInstance<House>("MyHouse").Number);
Console.WriteLine(source.GetInstance<Fruit>("MyFruit").Name);
var computer = source.GetInstance<object>("MyComputer", "Fast CPU", "Fast GPU");
Console.WriteLine((computer as Computer).Cpu);
Console.WriteLine((computer as Computer).Gpu);
Console.Read();
}
}
Since ExpandoObject is a dictionary, you can use this extension function:
public static object With(this IDictionary<string, object> obj, IDictionary<string,object> additionalProperties)
{
foreach (var name in additionalProperties.Keys)
obj[name] = additionalProperties[name];
return obj;
}
Usage:
var dynamicObj = new System.Dynamic.ExpandoObject().With(myDictionary);

C# dynamic classes

I'm talking about something similar to dynamic. This didn't answer my question, hence this question. I want to have a class that I can add properties to at runtime. It needs to be inherited from the type object.
I've seen inheriting from DynamicObject, but it didn't state how to add properties at run-time. Could some light be shed on this for me pls?
I have a class like this:
public class SomeModel : DynamicObject {
public string SomeMandatoryProperty {get; set;}
}
I'd like to add all properties from another class to this class at runtime. So eg.
SomeModel m = new SomeModel();
m = someOtherClass;
string hi = m.otherClassProp; //Property from other class is added.
string mandatory = m.SomeMandatoryProperty; //From the mandatory property set previously.
I think you are looking for ExpandoObject:
The ExpandoObject class enables you to
add and delete members of its
instances at run time and also to set
and get values of these members. This
class supports dynamic binding, which
enables you to use standard syntax
like sampleObject.sampleMember instead
of more complex syntax like
sampleObject.GetAttribute("sampleMember").
dynamic manager;
manager = new ExpandoObject();
manager.Name = "Allison Brown";
manager.Age = 42;
manager.TeamSize = 10;
You should be able to make use of ExpandoObject instead. An ExpandoObject can have members added or removed at runtime and has very nice support if you want to convert to XML etc.
From MSDN Documentation:
dynamic employee, manager;
employee = new ExpandoObject();
employee.Name = "John Smith";
employee.Age = 33;
manager = new ExpandoObject();
manager.Name = "Allison Brown";
manager.Age = 42;
manager.TeamSize = 10;
You'd want to use the ExpandoObject as you can dynamically add properties as needed. There isn't however a direct way to populate an instance with the values from another object easily. You'll have to add it manually using reflection.
Do you want to write a wrapper object where you could add properties to while still accessing the inner? You may want to consider it that way you don't have to manage two copies of values between two different object instances. I wrote a test class to wrap string objects to demonstrate how you can do this (similar to how the ExpandoObject works). It should give you an idea on how you can do this for your types.
class DynamicString : DynamicObject
{
static readonly Type strType = typeof(string);
private string instance;
private Dictionary<string, object> dynProperties;
public DynamicString(string instance)
{
this.instance = instance;
dynProperties = new Dictionary<string, object>();
}
public string GetPrefixString(string prefix)
{
return String.Concat(prefix, instance);
}
public string GetSuffixString(string suffix)
{
return String.Concat(instance, suffix);
}
public override string ToString()
{
return instance;
}
public override bool TryConvert(ConvertBinder binder, out object result)
{
if (binder.Type != typeof(string))
return base.TryConvert(binder, out result);
result = instance;
return true;
}
public override bool TryInvokeMember(InvokeMemberBinder binder, object[] args, out object result)
{
var method = strType.GetMethod(binder.Name, args.Select(a => a.GetType()).ToArray());
if (method == null)
{
result = null;
return false;
}
result = method.Invoke(instance, args);
return true;
}
public override bool TryGetMember(GetMemberBinder binder, out object result)
{
var members = strType.GetMember(binder.Name);
if (members.Length > 0)
{
var member = members.Single();
switch (member.MemberType)
{
case MemberTypes.Property:
result = ((PropertyInfo)member).GetValue(instance, null);
return true;
break;
case MemberTypes.Field:
result = ((FieldInfo)member).GetValue(instance);
return true;
break;
}
}
return dynProperties.TryGetValue(binder.Name, out result);
}
public override bool TrySetMember(SetMemberBinder binder, object value)
{
var ret = base.TrySetMember(binder, value);
if (ret) return true;
dynProperties[binder.Name] = value;
return true;
}
}
If you want to be adventurous, you can define your own meta objects to handle the bindings. You could end up with reusable meta objects for different types and simplify your code immensely. I've been playing with this for a while and have this so far. It doesn't handle dynamically adding properties yet. I won't be working on this any further but I'll just leave it here for reference.
class DynamicString : DynamicObject
{
class DynamicStringMetaObject : DynamicMetaObject
{
public DynamicStringMetaObject(Expression parameter, object value)
: base(parameter, BindingRestrictions.Empty, value)
{
}
public override DynamicMetaObject BindConvert(ConvertBinder binder)
{
if (binder.Type == typeof(string))
{
var valueType = Value.GetType();
return new DynamicMetaObject(
Expression.MakeMemberAccess(
Expression.Convert(Expression, valueType),
valueType.GetProperty("Instance")),
BindingRestrictions.GetTypeRestriction(Expression, valueType));
}
return base.BindConvert(binder);
}
public override DynamicMetaObject BindGetMember(GetMemberBinder binder)
{
System.Diagnostics.Trace.WriteLine(String.Format("BindGetMember: {0}", binder.Name));
var valueType = Value.GetType();
var self = Expression.Convert(Expression, valueType);
var valueMembers = valueType.GetMember(binder.Name);
if (valueMembers.Length > 0)
{
return BindGetMember(self, valueMembers.Single());
}
var members = typeof(string).GetMember(binder.Name);
if (members.Length > 0)
{
var instance =
Expression.MakeMemberAccess(
self,
valueType.GetProperty("Instance"));
return BindGetMember(instance, members.Single());
}
return base.BindGetMember(binder);
}
private DynamicMetaObject BindGetMember(Expression instance, MemberInfo member)
{
return new DynamicMetaObject(
Expression.Convert(
Expression.MakeMemberAccess(instance, member),
typeof(object)),
BindingRestrictions.GetTypeRestriction(Expression, Value.GetType())
);
}
}
public string Instance { get; private set; }
public DynamicString(string instance)
{
Instance = instance;
}
public override DynamicMetaObject GetMetaObject(Expression parameter)
{
return new DynamicStringMetaObject(parameter, this);
}
public override string ToString()
{
return Instance;
}
public string GetPrefixString(string prefix)
{
return String.Concat(prefix, Instance);
}
public string GetSuffixString(string suffix)
{
return String.Concat(Instance, suffix);
}
}

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