I am connecting you Google Places API to retrive results in the form of a JSON string. You can view the complete format of the string Here.
If you a look at it you will see that the actual results array starts after two elements which are html_attributions and next_page_token.
So When i try to deserialize it in this way:
var serializer = new JavaScriptSerializer();
var arr= serializer.Deserialize(result,typeof(string[]));
I get an empty array.
My question is how is there a way i can separate html_attributions and next_page_token fields and the pass the valid results array from the string to be deserialized?
I don't understand the part where you wish to seperate the html_attributions and the next_page_token.
Wouldn't it be sufficient to just deserialize the response with whatever properties that you need?
For example, you can deserialize the response to only retrieve the values that you desire;
// I represent the wrapper result
class Result
{
public List<string> html_attributions { get; set; }
public string next_page_token { get; set; }
public List<ResultItem> results { get; set; }
}
// I represent a result item
class ResultItem
{
public string id { get; set; }
public string name { get; set; }
}
// the actual deserialization
Result Deserialize(string json)
{
var serializer = new JavaScriptSerializer();
return serializer.Deserialize(json, typeof(Result));
}
Edit:
The reason that your deserialization doesn't return you a array of strings is because the response that you retrieve is infact an object and not an array, however the parameter within that object which is named results is an array. In order for you to deserialize more properties you'll have to define them in your "ResultItem" class, sorry for my poor naming here.
For instance, if you'd wish to also retrieve the icon property per result you'll have to add a property named "icon" of type string.
Meanwhile the property "photos" is an array, in order to deserialize it you'll have to create another class and add a property of type list/array of that newly created class, and it has to be named "photos" unless you use a different serializer or use DataContract and DataMember attributes (using the Name property for field mapping).
// the representation of a photo within a result item
class Photo
{
public int height { get; set; }
public List<string> html_attributions { get; set; }
public string photo_reference { get; set; }
public int width { get; set; }
}
// I represent a result item
class ResultItem
{
public string id { get; set; }
public string name { get; set; }
// the added icon
public string icon { get; set; }
// the added photos collection, could also be an array
public List<Photo> photos { get; set; }
}
Just look at the JSON result to figure out what other properties that you might want to add, for instance the "scope" property is an string whilst the "price_level" is an integer.
If I understand your comment correctly you're only interested in the actual results, you'll still have to deserialize the response correctly with its wrapper.
// the actual deserialization
List<ResultItem> Deserialize(string json)
{
var serializer = new JavaScriptSerializer();
var result = serializer.Deserialize(json, typeof(Result));
return result.results;
}
Edit2:
If you really want a string[] as a result you could simply take use of System.Linq using the code above.
string[] stringArray = result.results.Select(r => string.Format("id:{0} - name:{1}", r.id, r.name)).ToArray();
Edit3:
Instead of using the JavascriptSerializer you could use JObject functionality which can be found in the Newtonsoft.Json.Linq library.
var jsonObject = JObject.Parse(json);
string[] results = jsonObject.SelectTokens("results").Select(r => r.ToString()).ToArray();
This will give you an array of strings where each value within the array is the actual json string for each result.
If you however would like to query for the coordinates only:
var jsonObject = JObject.Parse(json);
var coordinates = jsonObject["results"]
.Select(x => x.SelectToken("geometry").SelectToken("location"))
.Select(x => string.Format("{0},{1}", (string)x.SelectToken("lat"), (string)x.SelectToken("lng")))
.ToArray();
This would give you an array of coordinates, eg:
[
"-33.867217,151.195939",
"-33.866786,151.195633",
...
]
Whatever approach you choose you'll be able to accomplish same results using either Newtonsoft or the .net serializer, whilst the Newtonsoft approach would allow you to query without creating strong types for deserialization.
I don't find the point of "[...] pass the valid results array from the string to be deserialized".
Maybe you need to switch to JSON.NET and do something like this:
// You simply deserialize the entire response to an ExpandoObject
// so you don't need a concrete type to deserialize the whole response...
dynamic responseEntity = JsonConvert.DeserializeObject<ExpandoObject>(
googlePlacesJson, new ExpandoObjectConverter()
);
// Now you can access result array as an `IEnumerable<dynamic>`...
IEnumerable<dynamic> results = responseEntity.results;
foreach(dynamic result in results)
{
// Do stuff for each result in the whole response...
}
Related
Below is a (slightly) stripped down response I get from a REST API upon successful creation of a new "job code" entry. I need to deserialize the response into some classes, but I'm stumped.
For reference, I'm using JSON.NET in .NET 3.5 (running in a SSIS script in SQL Server 2008 R2) to attempt my deserialization. Here's the JSON - which I obviously have no control over as it's coming from someone else's API:
{
"results":{
"jobcodes":{
"1":{
"_status_code":200,
"_status_message":"Created",
"id":444444444,
"assigned_to_all":false,
"billable":true,
"active":true,
"type":"regular",
"name":"1234 Main Street - Jackson"
},
"2":{
"_status_code":200,
"_status_message":"Created",
"id":1234567890,
"assigned_to_all":false,
"billable":true,
"active":true,
"type":"regular",
"name":"4321 Some Other Street - Jackson"
}
}
}
}
In my C# code, I do have a "JobCode" class defined which only partially maps the JSON values to properties - I'm not interested in all of the data that's returned to me:
[JsonObject]
class JobCode
{
[JsonProperty("_status_code")]
public string StatusCode { get; set; }
[JsonProperty("_status_message")]
public string StatusMessage { get; set; }
[JsonProperty("id")]
public string Id {get; set;}
[JsonProperty("name")]
public string Name { get; set; }
//-------------------------------------------------------------------------------
// Empty constructor for JSON serialization support
//-------------------------------------------------------------------------------
public JobCode() { }
}
I'm attempting to deserialize the data via this call:
newResource = JsonConvert.DeserializeObject<JobCode>(jsonResponse);
Where jsonResponse is the code outputted above.
When I execute the code, "newResource" always comes back as null - which is not unexpected because I know that there are actually multiple jobcodes in the data and this code is trying to deserialize it into a single JobCode object. I tried creating a new class called "JobCodes" that looks like this:
class JobCodes
{
[JsonProperty("jobcodes")]
public List<JobCode>_JobCodes { get; set; }
}
And then I tried calling this:
newResource = JsonConvert.DeserializeObject<JobCodes>(jsonResponse);
But the issue persists - my return object is null.
What's throwing me off, I think, is the presence of the "1" and "2" identifiers. I don't know how to account for their presence in my object design and/or usage of the JSON.NET class / property attributes like [JsonObject],[JsonProperty], etc.
When I run the JSON data through JSON2CSharp, it constructs some weird-looking classes, so that hasn't proven too effective. I've validated the JSON with several different validators and it all checks out - I just don't know what I'm missing here.
Ultimately, I'd like to return a List from the JSON data, but I'm stumped on what I need to do to make that happen.
Your problem is twofold:
You don't have a class defined at the root level. The class structure needs to match the entire JSON, you can't just deserialize from the middle.
Whenever you have an object whose keys can change, you need to use a Dictionary<string, T>. A regular class won't work for that; neither will a List<T>.
Make your classes like this:
class RootObject
{
[JsonProperty("results")]
public Results Results { get; set; }
}
class Results
{
[JsonProperty("jobcodes")]
public Dictionary<string, JobCode> JobCodes { get; set; }
}
class JobCode
{
[JsonProperty("_status_code")]
public string StatusCode { get; set; }
[JsonProperty("_status_message")]
public string StatusMessage { get; set; }
[JsonProperty("id")]
public string Id { get; set; }
[JsonProperty("name")]
public string Name { get; set; }
}
Then, deserialize like this:
RootObject obj = JsonConvert.DeserializeObject<RootObject>(json);
Working demo here
Excellent Answers!
For those out there that may need some more help with the JSON Class Configuration, try: http://json2csharp.com/#
An excellent way of Auto Generating the Classes!
Or even easier, in VS, Goto:
Edit -> Paste Special -> Paste as JSON Classes
Because you can't change the scheme of JSON, and you can't set constant No. of properties, I'd suggest you to use JObject
var jobject = JObject.Parse(json);
var results = jobject["results"];
var jobcodes = results["jobcodes"];
var output = jobcodes.Children<JProperty>()
.Select(prop => prop.Value.ToObject<JobCode>())
.ToList();
Warning: code assumes, that JSON is always in proper schema. You should also handle invalid schema (for example where property is not of JobCode scheme).
You can also deserialize your json to an object of your target class, and then read its properties as per normal:
var obj = DeSerializeFromStrToObj<ClassToSerialize>(jsonStr);
Console.WriteLine($"Property: {obj.Property}");
where DeSerializeFromStrToObj is a custom class that makes use of reflection to instantiate an object of a targeted class:
public static T DeSerializeFromStrToObj<T>(string json)
{
try
{
var o = (T)Activator.CreateInstance(typeof(T));
try
{
var jsonDict = JsonSerializer.Deserialize<Dictionary<string, string>>(json);
var props = o.GetType().GetProperties();
if (props == null || props.Length == 0)
{
Debug.WriteLine($"Error: properties from target class '{typeof(T)}' could not be read using reflection");
return default;
}
if (jsonDict.Count != props.Length)
{
Debug.WriteLine($"Error: number of json lines ({jsonDict.Count}) should be the same as number of properties ({props.Length})of our class '{typeof(T)}'");
return default;
}
foreach (var prop in props)
{
if (prop == null)
{
Debug.WriteLine($"Error: there was a prop='null' in our target class '{typeof(T)}'");
return default;
}
if (!jsonDict.ContainsKey(prop.Name))
{
Debug.WriteLine($"Error: jsonStr does not refer to target class '{typeof(T)}'");
return default;
}
var value = jsonDict[prop.Name];
Type t = Nullable.GetUnderlyingType(prop.PropertyType) ?? prop.PropertyType;
object safeValue = value ?? Convert.ChangeType(value, t);
prop.SetValue(o, safeValue, null); // initialize property
}
return o;
}
catch (Exception e2)
{
Debug.WriteLine(e2.Message);
return o;
}
}
catch (Exception e)
{
Debug.WriteLine(e.Message);
return default;
}
}
A complete working example class can be found in my enhanced answer to a similar question, here
I'm having trouble reading a JSON list of numbers into a c# int[] array.
I've tried several suggestions from SO, but none have worked.
How would I go about this using JSON.net?
Extract from JSON file:
{
"course": "Norsk",
"grades": [6, 3, 5, 6, 2, 8]
}
What I've tried in c#:
// Reads the JSON file into a single string
string json = File.ReadAllText(jfile);
Console.WriteLine(json);
// Parsing the information to a format json.net can work with
JObject data = JObject.Parse(json);
JToken jToken = data.GetValue("grades");
jGrades = jToken.Values<int>().ToArray();
and:
// Reads the JSON file into a single string
string json = File.ReadAllText(jfile);
Console.WriteLine(json);
// Parsing the information to a format json.net can work with
JObject data = JObject.Parse(json);
for (int o = 0; o < 6; o++) {
var grades = from p in data["Info"[i]] select (int)p["grades"[o]];
jGrades.Add(Convert.ToInt32(grades));
}
As you can see from the c# extracts, I've tried with both arrays and lists, but I can't get it to work.
With the first example (with an array) I get a System.NullRefrenceException, while with the List example, I get several errors, such as Unable to cast object of type 'whereselectlistiterator'2 [Newtonsoft.JSON] to type 'system.iconvertible'
Any help of tips are appreciated.
JObject.Parse(json) is your root object
JObject.Parse(json)["grades"] is the list/array
All you have to do is : converting the items to appropriate type
var list = JObject.Parse(json)["grades"].Select(x => (int)x).ToArray();
You can also declare a class
public class RootObject
{
public string course { get; set; }
public List<int> grades { get; set; }
}
and deserialize whole object as
var myobj = JsonConvert.DeserializeObject<RootObject>(json);
var grade = myobj.grades[0];
I would typically define a class with the relevant properties and simply convert the object.
public class CourseReport
{
public string Course { get; set; }
public ICollection<int> Grades { get; set; }
}
// Reads the JSON file into a single string
string json = File.ReadAllText(jfile);
Console.WriteLine(json);
// Parsing the information to a format json.net can work with
var courseReport = JsonConvert.DeserializeObject<CourseReport>(json);
foreach (var grade in courseReport.Grades)
{
Console.WriteLine(grade);
}
I have a web service which return response in JSON format as below.
{"123":{"Name":"Abcd", "Age":"30"},"231":{"Name":"xyz", "Age":"20"}, "543":{"Name":"pqr", "Age":"35"}}
I want to deserialize this response in C# and wants to display it.
How can I do with Newtonsoft.Json library.
Please help me.
I'm going to assume that "123", "231", and "543" are identifiers and not constant property names. In that case what you have is a dictionary of objects. First, define a class that maps to the object.
public class Something
{
public string Name { get; set; }
public string Age { get; set; }
}
Then deserialize into a dictionary of those objects.
var whatever = JsonConvert.DeserializeObject<Dictionary<string, Something>>(json);
I'm having troubles with some Deserialization because I'm not receiving an object like I'm used to but an array. Lets to the code, how I've being doing it:
JSON received:
[{"gcm_regID":"fsdf2156fw62f1wfwe512g"}]
Deserialization
var result = JsonConvert.DeserializeObject<Gcm>(response);
Handlers Tried:
public class Gcm
{
public List<Gcm_reg> gcm_regID { get; set; }
}
public class Gcm_reg
{
public string gcm_regID { get; set; }
}
I've tried just the Gcm_reg as well and nothing seems to work. How can I deserialize this? By the way, I'm using the newsoft JSON.
Best regards,
IEnumerable<Gcm_reg> result = JsonConvert.DeserializeObject<IEnumerable<Gcm_reg>>(response);
You can deserialize the object as an array or IEnumerable
Object should be like
public class Gcm
{
public string gcm_regID { get; set; }
}
So Try it
var result = JsonConvert.DeserializeObject<IEnumerable<Gcm>>(response);
You can directly generate classes from Json by using link
To create same type of object
var outputList = new List<Gcm>();
//loop through this part based on number of input
var itemToAdd = new Gcm();
itemToAdd .regID = 'something';
outputList.Add(itemToAdd );
and send outputList to server.
I have a JSON stream that sends collections looking like this:
[{"channel":"24e67e0d-1cad-4cc09e7af8523ef460fe",
"op":"private",
"origin":"broadcast",
"stamp":1388680103991749},
"13886801043507640",
"24e67e0d-1cad-4cc0-9e7a-f8523ef460fe"]
The first object is no problem, but the last two ones ("13886801043507640" and "24e67e0d-1cad-4cc0-9e7a-f8523ef460fe") make Json.Net throw exceptions they don't even follow the format {field:name,field:name}.
How can I handle these objects properly (or at least discard them) using Json.Net?
Cheers, any input is appreciated.
Here is one approach to extract the object data from the JSON using Json.Net.
First define a class for the object:
class Item
{
public string channel { get; set; }
public string op { get; set; }
public string origin { get; set; }
public long stamp { get; set; }
}
Then use Json.Net's LINQ-to-JSON API to parse and filter the array, extracting only the object part:
JArray array = JArray.Parse(json);
Item item = array.Children<JObject>().First().ToObject<Item>();
If there can be multiple objects, you can get them into a list like this (assuming they all have the same structure):
List<Item> items = array.Children<JObject>()
.Select(jo => jo.ToObject<Item>())
.ToList();
Similarly, you can get the string values from the array like this:
List<string> strings = array.Children<JValue>()
.Select(jv => jv.ToString())
.ToList();