Jquery/C# Making a webService call errors out: cannot be serialized because it does not have a parameterless constructor

Question

Here's my call:

CallMfttService("ServiceLayer/FieldingManager.asmx/GetUICs",null, SetUicValues);

Here's the WebMethod:

[WebMethod]
    [ScriptMethod]
    public List<string> GetUICs()
    {
        UserManager user = new UserManager();
        var currentUser = user.GetUser(Security.FieldingToolPrincipal.Current.Identity.Name);
        List<string> uics = new List<string>();
        uics = Data.FieldingManager.SelectUicByJpm(currentUser.Organization);

        return uics;
    }

I'm not exactly sure what the problem is.. I know it obviously doesn't like sending no paramters..I really don't know though.

Answer 1

try replacing null with new object[0] in your call

CallMfttService("ServiceLayer/FieldingManager.asmx/GetUICs",new object[0], SetUicValues);

Answer 2

Have you got a Stack Trace?

Answer 3

The problem is most likely this:

Data.FieldingManager.SelectUicByJpm(currentUser.Organization);

The object you're returning, "uics", probably doesn't have a blank constructor. That is, a new with no parameters:

new UicObject();

Giving it one should fix your problem.

Answer 4

I found out the I need to send an empty parameter to the method.

CallMfttService("ServiceLayer/FieldingManager.asmx/GetUICs", "{}", SetUicValues);

the "{}" fixed the issue.. thanks for the replies