Question

I get the InvalidOperationException when I try to deserialize a json string for my person object. It states that my Person object is not supported for deserialization

  [DataContract]
  public class Person
  {
    public string FirstName {get;set;}
    public string LastName {get; set;}
    public int Id {get; set;}
  }

An example of the json string

[{"name":"FirstName","value":"John"},{"name":"LastName","value":"Doe"},{"name":"Id","value":"1001"}]

And here’s where I get my exception

  Person p = new JavaScriptSerializer().Deserialize<Person>(json);

I’ve tried the DataContractJsonSerializer too without much luck.

Answer 1

I have tested your code and found the problem.

Your jSon string provided a array of Person. Change to Person[] and it will work.

Here is my test code

string json = "[{\"name\":\"FirstName\",\"value\":\"John\"},{\"name\":\"LastName\",\"value\":\"Doe\"},{\"name\":\"Id\",\"value\":\"1001\"}]";
Person[] p = new JavaScriptSerializer().Deserialize<Person[]>(json);

Update

Your jSon string is not in the right format. The Deserializer cant find the property to assign your values.

The right would be.

{ "NameOfProperty" : "ValueOfProperty" }

This is a right format

[{"FirstName":"Jon", "LastName":"Doe"}, {"FirstName":"Jon", "LastName":"Doe"}]

Test Code

string json = "[{\"FirstName\":\"Jon\", \"LastName\":\"Doe\"}, {\"FirstName\":\"Jon\", \"LastName\":\"Doe\"}]";
Person[] p = new JavaScriptSerializer().Deserialize<Person[]>(json);