无法返回WCF中的词典列表

Question

I am new in WCF. I am trying to return list of dictionary in wcf.

Here is my code.

 public class Service1 : IService1
 {
   public List<Dictionary<string, object>> GetData(string query)
    {
          List<Dictionary<string, object>> rows = new List<Dictionary<string, object>>();
          ...
          ...
          return rows;
    }

 }

public interface IService1
{
    [WebGet()]
    [OperationContract]
    List<Dictionary<string, object>> GetData();
}

If I return return string it will work properly I want to return list like this.

Answer 1

You have to create class and set attribute KnownType .

 [DataContract]
[KnownType(typeof(List<Dictionary<string, object>>))]
public class Foo
{
    [DataMember]
    public IDictionary<String, Object> Inputs { get; set; }
}

Now instead List<Dictionary<string, object>> use List<Foo> You can do like this sample.

IService

        [OperationContract]
   [WebInvoke(Method = "GET",
   ResponseFormat = WebMessageFormat.Json,
   BodyStyle = WebMessageBodyStyle.Bare,
   UriTemplate = "GetData")]
    List<Foo> GetData();

Service

    public List<Foo> GetData()
    {
        List<Foo> rows = new List<Foo>();
        var x = new Dictionary<string, object>();
        x.Add("sss","sss");
        x.Add("zzz", "zzz");
        x.Add("aaa", "aaa");
        var z = new Foo();
       z.Inputs = x;

        rows.Add(z);
        rows.Add(z);
        return rows;
    }