I am trying to use one web service which returns demanded data in json format. Now the actual point is I can fetch the data from the particular web service url in string.
string url= #"http://api.oodle.com/api/v2/listings?key=TEST®ion=chicago&category=vehicle&format=json";
string jsonString = new WebClient().DownloadString(url);
Now the point is I get the data in string (in JSON format). But I dont know how to convert the string into JSON string and how to fetch data from this string.
Let me give you example so you can easily understand
if my jsonString is like
{
"current":{
"region":{
"id":"chicago",
"name":"Chicago"
},
"category":{
"id":"vehicle",
"name":"Cars & Vehicles",
"abbrev":"Vehicles"
},
"start":1,
"num":10
}
}
How can i get region_name from that string ? Hope you understand me ! Try to use Test Link !
Add a reference to System.Web and then add to your using section
using System.Web.Script.Serialization;
Then (using your example json string)
string jsonString = "{\"current\":{\"region\":{\"id\":\"chicago\",\"name\":\"Chicago\"},\"category\":{\"id\":\"vehicle\",\"name\":\"Cars & Vehicles\",\"abbrev\":\"Vehicles\"},\"start\":1, \"num\":10}}";
JavaScriptSerializer serializer = new JavaScriptSerializer();
CurrentRecord currentRecord = serializer.Deserialize<CurrentRecord>(jsonString);
string regionName = currentRecord.current.region.name;
Also add the following classes to your project:
[Serializable]
public class CurrentRecord
{
public current current;
}
[Serializable]
public class current
{
public region region;
public category category;
public int start;
public int num;
}
[Serializable]
public class region
{
public string id;
public string name;
}
[Serializable]
public class category
{
public string id;
public string name;
public string abbrev;
}
Are you processing the JSON return string in Java, or JavaScript?
If you are processing the JSON response string in Java, you may make use of GSON. Here is a tutorial showing you how: Parsing a JSON String into an object with GSON easily.
For your case, you need a class like:
class Current{
private Region region;
private Category category;
private int start;
private int num;
// getters and setters
class Region{
private String id;
private String name;
// getters and setters
}
class Category{
private String id;
private String name;
private String abbreviation;
// getters and setters
}
}
Else if you are processing this JSON response String in Javascript, then you can have a look at this: http://www.json.org/js.html
alert(jsonReturnString.current.region.name);
Related
I am trying to get some currency values from an api. it's returning the data in the following format:
{"PKR_PKR":{"val":1}}
I want to show this value in textbox but there's an error
"Object reference not set to an instance of object".
I've tried the following code:
try
{
string endPoint = #"http:urlhere";
string ResultJson = "";
using (WebClient wc = new WebClient())
{
ResultJson = wc.DownloadString(endPoint);
}
JsonData values = JsonConvert.DeserializeObject<JsonData>(ResultJson);
txtBalanceRate.Text = values.CurrencyValue.ToString();
}
catch (Exception ex) { }
Class code:
class JsonData
{
public object CurrencyValue { get; set; }
}
**
UPDATE
**
Note: I can not update PKR_PKR Class becuase every time the name of variable is different for different currencies i.e. it can be USD_PKR , EUR_PKR etc
How can I resolve this?
FOLLOWING IS THE UPDATED CODE:
try
{
string endPoint = #"http://free.currencyconverterapi.com/api/v5/convert?q="+ddlCurrency.SelectedValue.ToString()+"_PKR&compact=y";
string ResultJson = "";
using (WebClient wc = new WebClient())
{
ResultJson = wc.DownloadString(endPoint);
}
RootObject rootObject = JsonConvert.DeserializeObject<RootObject>(ResultJson);
txtBalanceRate.Text = rootObject.PKR_PKR.val.ToString();
}
catch (Exception ex)
{
}
public class PKRPKR
{
public int val { get; set; }
}
public class RootObject
{
public PKRPKR PKR_PKR { get; set; }
}
If you are going to have dynamic object then you should try this out
dynamic data = Newtonsoft.Json.JsonConvert.DeserializeObject(json);
Type typeOfDynamic = data.GetType();
if( typeOfDynamic.GetProperties().Where(p => p.Name.Equals("PKR_PKR")).Any())
{
console.WriteLine(data.PKR_PKR.val);
}
else if( typeOfDynamic.GetProperties().Where(p => p.Name.Equals("USD_PKR")).Any())
{
console.WriteLine(data.USD_PKR.val);
}
else if( typeOfDynamic.GetProperties().Where(p => p.Name.Equals("EUR_PKR")).Any())
{
console.WriteLine(data.EUR_PKR.val);
}
above way is not tried and tested but you can have try like this as you json is dynamic.
Above way is checking property exist or not and get val from dynamci object
Your class structure is incorrect can you please try below class structure
public class PKRPKR
{
public int val { get; set; }
}
public class RootObject
{
public PKRPKR PKR_PKR { get; set; }
}
RootObject rootObject = JsonConvert.DeserializeObject<RootObject>(json);
Console.WriteLine(rootObject.PKR_PKR.val);
Mostly if you see above class structure , you josn each node is represent as class, but I dont go in much detail as Visual studio can do it for me.
When comes to json to object conversion ,I make use of utility provided by Visual studio. which does conversion of json string to proper class structure. here is image of it
Read how to do it full here :
Visual Studio Generate Class From JSON or XML
If you dont have visual studio with this feature you can use this online utility : json2csharp
Note: I can not update PKR_PKR Class becuase evert time the name of
variable is different for different currencies i.e. it can be USD_PKR
, EUR_PKR etc How can I resolve this?
SOLUTION
if json string {"PKR_PKR":{"val":1}} is fixed in your case, you can use following solution for any currency name you got.
static void Main(string[] args)
{
string json1 = "{ \"PKR_PKR\":{ \"val\":1}}";
string json2 = "{ \"USD_PKR\":{ \"val\":2}}";
string json3 = "{ \"EUR_PKR\":{ \"val\":3}}";
JToken token1 = (JToken)JsonConvert.DeserializeObject(json1);
Console.WriteLine(token1.First().First()["val"]);
JToken token2 = (JToken)JsonConvert.DeserializeObject(json2);
Console.WriteLine(token2.First().First()["val"]);
JToken token3 = (JToken)JsonConvert.DeserializeObject(json3);
Console.WriteLine(token3.First().First()["val"]);
Console.ReadLine();
}
I think your receiving object should contain a dictionary, not a single string:
Check this
Or you have to improve your object structure implementing a root item which contains a PKR_PKR sub object
I have a JsonString:
"baseAbilities":"[{"baseId":1,"name":"Focused Elemental Strike"}]"
I want to make it:
"baseAbilities":[{"baseId":1,"name":"Focused Elemental Strike"}]
So the it is easy for JSON utility to deserialise it. Any suggestions
EDIT:
This is basically a json object in the following Json String:
{"data”: [{"id":9,"name":"Sam5","baseAbilities":"[{\"baseId\":1,\"name\":\"Focused Elemental Strike\"},{\"baseId\":9,\"name\":\"Cleanse\"}]"]}
The backend developer saved JSON in a column baseAbilities as a string. Now I don't have the access to Back end APIs. So i need to convert this string baseAbilities to JSON so that I can access objects inside it.
Now I use these classes to decode JSON:
[System.Serializable]
class GetBAResult
{
public List<bounceAbilityData> data;
}
[System.Serializable]
class bounceAbilityData
{
public int id;
public string name;
public string baseAbilities;
}
And this is how I decode JSON:
GetBAResult P = JsonUtility.FromJson<GetBAResult>(w.text);
for (int i = 0; i < P.data.Count; i++)
{
Debug.Log(P.data[i].name);
GameObject layoutGroupNameButton = (GameObject)Instantiate(prefabBAButton);
layoutGroupNameButton.transform.SetParent(ParentPanel, false);
layoutGroupNameButton.GetComponentInChildren<Text>().text = P.data[i].name;
layoutGroupNameButton.GetComponent<BounceAbilityButton>().id = P.data[i].id;
layoutGroupNameButton.GetComponent<BounceAbilityButton>().name = P.data[i].name;
Debug.Log(P.data[i].baseAbilities);
}
I need to get things inside baseAbilities such as "baseID" and "name"
Have you tried this?
JObject json = JObject.Parse(str);
documentation
With a class set of
[System.Serializable]
class GetBAResult
{
public List<bounceAbilityData> data;
}
[System.Serializable]
class bounceAbilityData
{
public int id;
public string name;
public List<BaseAbilities> baseAbilities;
}
[System.Serializable]
class BaseAbilities
{
public int baseId;
public string name;
}
You can then use the following to Deserialize your JSON to an instance of GetBAResult
string json = "{\"data\":[{\"id\":9,\"name\":\"Sam5\",\"baseAbilities\":[{\"baseId\":1,\"name\":\"Focused Elemental Strike\"},{\"baseId\":9,\"name\":\"Cleanse\"}]}]}";
GetBAResult myObject = JsonUtility.FromJson<GetBAResult>(json);
BaseAbilities abilities = myObject.data[0].baseAbilities[0];
You can read more about JSON Deserialization here on the Unity Documentation
https://docs.unity3d.com/Manual/JSONSerialization.html
The original questions says that you want to change:
"baseAbilities":"[{"baseId":1,"name":"Focused Elemental Strike"}]"
to
"baseAbilities":[{"baseId":1,"name":"Focused Elemental Strike"}]
Basically, you want to remove the " before the [{" then remove the final " at the end of the json string. The problem is that even after you do this, "baseAbilities":[{"baseId":1,"name":"Focused Elemental Strike"}] cannot be serialized to json.
You need to add { in front of it and } at the end of it.
The final string after adding { in front of it and } at the end is:
{"baseAbilities":[{"baseId":1,"name":"Focused Elemental Strike"}]}
The fixJson function below fixes those problems and this is how to use it:
[System.Serializable]
public class BaseAbility
{
public int id;
public string name;
}
[System.Serializable]
public class GetBAResult
{
public List<BaseAbility> baseAbilities;
}
void Start()
{
// StartCoroutine(RespawnPlayer());
string fixedJson = fixJson(w.text);
//string fixedJson = fixJson("\"baseAbilities\":\"[{\"id\":1,\"name\":\"Focused Elemental Strike\"}]\"");
Debug.Log("Fixed Json: " + fixedJson);
GetBAResult P = JsonUtility.FromJson<GetBAResult>(fixedJson);
Debug.Log("Count Json: " + P.baseAbilities.Count);
for (int i = 0; i < P.baseAbilities.Count; i++)
{
Debug.Log("Name: " + P.baseAbilities[i].name);
Debug.Log("Base ID: " + P.baseAbilities[i].id);
}
}
string fixJson(string jsonToFix)
{
//First srting with `"` that will be removed
const string firstString = "\"baseAbilities\":\"";
//Last string with `"` that will be removed
const string lastString = "\"";
//String that will be used to fix the "baseAbilities":"[ with the `"`
const string fixedFirstString = "\"baseAbilities\":";
//Get the first Index of firstString
int firstIndex = jsonToFix.IndexOf(firstString);
//Remove First Index of `firstString`
jsonToFix = jsonToFix.Remove(firstIndex, firstString.Length);
int lastIndex = jsonToFix.LastIndexOf(lastString);
//Remove everything from Last `lastString` to the end
jsonToFix = jsonToFix.Remove(lastIndex);
//Append the correct/fixed string without `"` to the beginning of the json data
jsonToFix = fixedFirstString + jsonToFix;
//Add `{` to the begging and `}` to the end of the json data
jsonToFix = "{" + jsonToFix + "}";
return jsonToFix;
}
Let's say you have a class like this:
using System;
using System.Collections.Generic;
using UnityEngine;
public class JsonTest : MonoBehaviour
{
[Serializable]
public class Ability
{
public int baseId;
public string name;
public Ability(int _baseId, string _name)
{
baseId = _baseId;
name = _name;
}
}
public class Abilities
{
public List<Ability> baseAbilities;
public Abilities(List<Ability> _baseAbilities)
{
baseAbilities = _baseAbilities;
}
}
void Start()
{
List<Ability> list = new List<Ability>();
list.Add(new Ability(1, "Focused Elemental Strike"));
list.Add(new Ability(2, "Another ability"));
Abilities baseAbilities = new Abilities(list);
string serializedAbilites = JsonUtility.ToJson(baseAbilities);
Debug.Log(serializedAbilites);
Abilities deserializedAbilites = JsonUtility.FromJson<Abilities>(serializedAbilites);
}
}
You have an Ability class marked as Serializable containing and id and a name.
You have another class Abilities used as a wrapper for a list of abilities.
You can then serialize a list of abilities using JsonUtility.ToJson(). Which will give you the following string:
{
"baseAbilities": [
{
"baseId": 1,
"name": "Focused Elemental Strike"
},
{
"baseId": 2,
"name": "Another ability"
}
]
}
And of course you can deserialize it using JsonUtility.FromJson().
Is this what your looking for ?
I've been searching for the past 4 hours for ways on how to tackle this problem, and I've not yet found a solution.
I'm building an API with .NET and wish to parse JSON information that is sent back from API calls.
My current approach does the following:
private void PostNewPlayer(HttpContext context)
{
// Create the serializer
context.Request.InputStream.Position = 0;
DataContractJsonSerializer json = new DataContractJsonSerializer(typeof(ASPlayer));
ASPlayer p = (ASPlayer)json.ReadObject(context.Request.InputStream); <-- Exception here
Int32 playerId = ASPlayerManager.InsertNewPlayer(p);
}
But I currently get an Exception at the indicated line. I have made sure my class implements the correct serialization namespaces:
using System.Runtime.Serialization;
using System.IO;
using System.Runtime.Serialization.Json;
The class I am trying to serialize has had its DataContract and Member fields set accordingly:
[DataContract]
public class ASPlayer
{
[DataMember]
private string _name;
public string player_name
{
get { return _name; }
set { _name = value; }
}
[DataMember]
private string _location;
public string player_location
{
get { return _location; }
set { _location = value; }
}
// Other vars
...
public ASPlayer(string name, string location)
{
_name = name;
_location = location;
}
}
However, when I use a HTTP client such as Postman to make a request I get the error stated in the question title
I think you marked the wrong variables, this:
[DataMember]
private string _name;
public string player_name
should be this:
private string _name;
[DataMember]
public string player_name
The answer was a very bad mistake on my behalf, but for those who encounter this in future make sure you send your JSON object in Postman through the Raw field. In my case I simply did:
{
"player_name": "Test",
"player_location": "EUW",
"player_wins":10,
"player_draws":10,
"player_losses":15,
"player_points":20
}
This fixed it
I need to use some JSON data with a C# application, but i can't figure a way of getting the data.
I'm using SOCKET.IO, and here is a sample of a raw json string that is recieved
`socket.On("recieved", (data) =>
{
MessageBox.Show(data.Json.ToJsonString());
//outputs : {'name':'received','args':[{'data':'somedata'}]}
//get values from data
}`<br>
and i need to retrieve the value of 'data'
Look at the examples in the SocketIO4Net archive.
Define a class
using Newtonsoft.Json;
namespace TestProject
{
[JsonObject(MemberSerialization.OptIn)]
public class JSonData
{
[JsonProperty]
public string data { get; set; }
public JSonData()
{
}
public string ToJsonString()
{
return JsonConvert.SerializeObject(this);
}
public static JSonData Deserialize(string jsonString)
{
return JsonConvert.DeserializeObject<JSonData>(jsonString);
}
}
}
And after you get data like this :
JSonData JData = data.Json.GetFirstArgAs<JSonData>();
Ok i got that working, but if i want all args in JSON string {data:"somedata",anotherdata:'someanotherdata'} and get 'anotherdata', i tried `
JSonData part = data.Json.GetArgsAs();
Sorry for the double answers, but this did it for me
private Newtonsoft.Json.Linq.JObject get_data(SocketIOClient.Messages.JsonEncodedEventMessage data)
{
var inputdata = data;
dynamic jsondata = inputdata.GetArgsAs<Object>();
jsondata = jsondata[0];
return jsondata;
}
and then just do
dynamic json = get_data(data.Json);
I have a string with the following structure:
Student Name________AgeAddress_______________________Bithday___Lvl
Example:
Jonh Smith 016Some place in NY, USA 01/01/2014L01
As you can see, there is no delimited character like | or ,
Also, there is no space between fields (if you check, there is no space between Age/Address and Birthday/Level.
The size of each field is static so if data's length is less then it will contains white spaces.
I have a class that need to be filled with that information:
public class StudentData
{
public char[] _name = new char[20];
public string name;
public char[] _age = new char[3];
public string age;
public char[] _address = new char[30];
public string address;
public char[] _bday = new char[10];
public string bday;
public char[] _level = new char[3];
public string level;
}
Is there any way to do this automatically and dynamically?
I mean I really don't want to code like this:
myClass.name = stringLine.substring(0,19);
myClass.age = stringLine.substring(20,22);
That's because I have way more fields that the ones added in this example & way more string lines with other different data.
Update: There were supposed to be a lot of spaces between "Smith" and "016", but I don't know how to edit it.
Update2: If I use StringReader.Read() I can evade to use substring and indexes, but it isn't still so dynamically because I would need to repeat those 3 lines for each field.
StringReader reader = new StringReader(stringLine);
reader.Read(myClass._name, 0 myClass._name.Length);
myClass.name = new string(myClass._name);
Given your requirement I came up with an interesting solution. All be-it it may be more complex and longer than using the String.SubString() method as stated.
However this solution is transferable to other types and other string. I used a concept of Attributes, Properties, and Reflection to parse a string by a Fixed Length and setting the class Properties.
Note I did change your StudentData class to follow a more conventional coding style. Following this handy guide on MSDN: http://msdn.microsoft.com/en-us/library/xzf533w0(v=vs.71).aspx
Here is the new StudentData class. Note it uses the properties as opposed to fields. (Not discussed here).
public class StudentData
{
string name;
string age;
string address;
string bday;
string level;
[FixedLengthDelimeter(0, 20)]
public string Name { get { return this.name; } set { this.name = value; } }
[FixedLengthDelimeter(1, 3)]
public string Age { get { return this.age; } set { this.age = value; } }
[FixedLengthDelimeter(2, 30)]
public string Address { get { return this.address; } set { this.address = value; } }
[FixedLengthDelimeter(3, 10)]
public string BDay { get { return this.bday; } set { this.bday = value; } }
[FixedLengthDelimeter(4, 3)]
public string Level { get { return this.level; } set { this.level = value; } }
}
Note on each of the properties there is an Attribute called FixedLengthDelimeter that takes two parameters.
OrderNumber
FixedLength
The OrderNumber parameter denotes the order in the string (not the position) but the order in which we process from the string. The second parameter denotes the Length of the string when parsing the string. Here is the full attribute class.
[AttributeUsage(AttributeTargets.Property, AllowMultiple = false)]
public sealed class FixedLengthDelimeterAttribute : Attribute
{
public FixedLengthDelimeterAttribute(int orderNumber, int fixedLength)
{
this.fixedLength = fixedLength;
this.orderNumber = orderNumber;
}
readonly int fixedLength;
readonly int orderNumber;
public int FixedLength { get { return this.fixedLength; } }
public int OrderNumber { get { return this.orderNumber; } }
}
Now the attribute is simple enough. Accepts the two paramters we discussed eariler in the constructor.
Finally there is another method to parse the string into the object type such as.
public static class FixedLengthFormatter
{
public static T ParseString<T>(string inputString)
{
Type tType = typeof(T);
var properties = tType.GetProperties(BindingFlags.Instance | BindingFlags.Public); //;.Where(x => x.GetCustomAttributes(typeof(FixedLengthDelimeterAttribute), false).Count() > 0);
T newT = (T)Activator.CreateInstance(tType);
Dictionary<PropertyInfo, FixedLengthDelimeterAttribute> dictionary = new Dictionary<PropertyInfo, FixedLengthDelimeterAttribute>();
foreach (var property in properties)
{
var atts = property.GetCustomAttributes(typeof(FixedLengthDelimeterAttribute), false);
if (atts.Length == 0)
continue;
dictionary[property] = atts[0] as FixedLengthDelimeterAttribute;
}
foreach (var kvp in dictionary.OrderBy(x => x.Value.OrderNumber))
{
int length = kvp.Value.FixedLength;
if (inputString.Length < length)
throw new Exception("error on attribute order number:" + kvp.Value.OrderNumber + " the string is too short.");
string piece = inputString.Substring(0, length);
inputString = inputString.Substring(length);
kvp.Key.SetValue(newT, piece.Trim(), null);
}
return newT;
}
}
The method above is what does the string parsing. It is a pretty basic utility that reads all the properties that have the FixedLengthDelimeter attribute applied a Dictionary. That dictionary is then enumerated (ordered by OrderNumber) and then calling the SubString() method twice on the input string.
The first substring is to parse the next Token while the second substring resets the inputString to start processing the next token.
Finally as it is parsing the string it is then applying the parsed string to the property of the class Type provided to the method.
Now this can be used simply like this:
string data1 = "Jonh Smith 016Some place in NY, USA 01/01/2014L01";
StudentData student = FixedLengthFormatter.ParseString<StudentData>(data1);
What this does:
Parses a string against property attributes in a fixed length format.
What this does not do:
It does convert the parsed strings to another type. Therefore all the properties must be a string. (this can be easily adapted by adding some type casting logic in).
It is not well tested. This is only tested against a few samples.
It is not by all means the only or best solution out there.
You could use FileHelpers library (NuGet).
Just define the structure of your input file with attributes:
[FixedLengthRecord]
public class StudentData
{
[FieldFixedLength(20)]
[FieldTrim(TrimMode.Right)]
public string name;
[FieldFixedLength(3)]
public string age;
[FieldFixedLength(30)]
[FieldTrim(TrimMode.Right)]
public string address;
[FieldFixedLength(10)]
public string bday;
[FieldFixedLength(3)]
public string level;
}
Then simply read the file using FileHelperEngine<T>:
var engine = new FileHelperEngine<StudentData>();
var students = engine.ReadFile(filename);