WCF AJAX Response fail when Using System.Array as a DataMember

Question

When i m trying to get Sytem.Array As data member in Json Class object it gives failure response .

My WCf web-service i am using following method userActivities which return class Activity.I have set parameter in class Activity from Ajax .

[ServiceContract]
public interface IMyService
{
    [OperationContract]
    [WebInvoke(Method = "POST", BodyStyle = WebMessageBodyStyle.Wrapped, ResponseFormat = WebMessageFormat.Json)]
    Activity userActivities(Activity activity, string action);
}

[DataContract]
partial class Activity
{

}

And in the MyService.cs Class of Service is

public Activity userActivities(Activity activity, string action)
{
    if (action.ToLower() == "myactivities")
    {
      activity.get_MyActivities();
    }
    return activity;
}

And Class Activity is :

[DataMember]
public int userID;

[DataMember]
public Array _getList_MyActivities;

public void get_MyActivities()
{
    _DL_Activity = new DL_Activity();
    if (this.userID > 0)
        this._getList_MyActivities = _DL_Activity.get_MyActivity(this.userID);

}

Answer 1

Got this post. According to this try decorating your service with ServiceKnownType.

Something like this

[ServiceContract]
[ServiceKnownType(typeof(string))]
[ServiceKnownType(typeof(string[]))]
public interface IMyService

According to your comment you are storing different data types in the array, I guess you will need to put typeof for all items in array as ServiceKnownType.

Hope this works for you.