Json.NET deserializing custom object returns null

Question

I am having trouble in converting a JSON string to a C# object with Json.NET.

I used the AJAX call .ashx

$.ajax({
    url: "/Handler/Handler.ashx?WorkType=SaveData",
    type: "POST",
    data: JSON.stringify({ 'DataInfo': Info }),
    //data: "{'DataInfo':" + JSON.stringify(Info) + "}",
    dataType: "json",
    success: function (data, textStatus, jqXHR) {
        if (data.Result) {

        }
    },
    error: function (jqXHR, textStatus, errorThrown) {
        alert("Error '" + jqXhr.status + "' (textStatus: '" + textStatus + "', errorThrown: '" + errorThrown + "')");
    }
});

And my Json String is like

{
   "DataInfo": [
      {
         "EditType": "Create",
         "CustCode": "SSG",
         "KeyNoStr": "rgrg",
         "Requester": "rgrg",
         "VerificationCode": "VAVBZ",
         "Databody": "TESt123",
         "HasMap": false,
         "IsColse": false,
         "HasOrder": false,
         "IsUrgent": true
      }
   ]
}

and my .ashx Server side code is like..

public class DataInfo
{
    public string EditType { get; set; } 
    public string CustCode { get; set; }
    public string KeyNoStr { get; set; }
    public string Requester { get; set; }
    public string VerificationCode { get; set; }
    public string Databody { get; set; }
    public string HasMap { get; set; }
    public string IsColse { get; set; }
    public string HasOrder { get; set; }            
    public string IsUrgent { get; set; }
}

main function in .ashx

public void ProcessRequest(HttpContext context)
{
    Request = context.Request;
    Response = context.Response;

    string lv_strResult = string.Empty;

    DataInfo lv_oInfo = JsonConvert.DeserializeObject<DataInfo >((new StreamReader(Request.InputStream)).ReadToEnd());
}

What I am doing wrong?

Answer 1

That's because that JSON object is an Array of DataInfo , so you need to deserialize using these classes

public class DataInfo
{
    public string EditType { get; set; }
    public string CustCode { get; set; }
    public string KeyNoStr { get; set; }
    public string Requester { get; set; }
    public string VerificationCode { get; set; }
    public string Databody { get; set; }
    public bool HasMap { get; set; }
    public bool IsColse { get; set; }
    public bool HasOrder { get; set; }
    public bool IsUrgent { get; set; }
}

public class RootObject
{
    public List<DataInfo> DataInfo { get; set; }
}

//your method
public void ProcessRequest(HttpContext context)
{
    Request = context.Request;
    Response = context.Response;

    string lv_strResult = string.Empty;

    DataInfo lv_oInfo = JsonConvert.DeserializeObject<RootObject>((new StreamReader(Request.InputStream)).ReadToEnd());
 }

Answer 2

Your JSON represents structure with one property named DataInfo of type List<DataInfo>

So you need to replace DataInfo lv_oInfo = JsonConvert.DeserializeObject<DataInfo >((new StreamReader(Request.InputStream)).ReadToEnd()); with

var jobject = (JObject)JsonConvert.DeserializeObject((new StreamReader(Request.InputStream)).ReadToEnd());
var di_json = jobject["DataInfo"].ToString();   // Dirty but this is the main idea
var data_infos = JsonConvert.DeserializeObject<List<DataInfo>>(di_json);

This is not the best code in the world because of double deserialization, but it shows the idea.