web method return type

[niraj]

Hi;

Can WebMethod return Interface type?
I am getting System.InvalidOperationException
Followin is code...

public interface IDBData
{

/// <summary>
/// PrimaryKey value
/// </summary>
long ID
{
get;
set;
}
}

//In WebService class
[WebMethod(Description="Get data from DB, given primaryKey & dataType")]
public IDBData Retrieve(long primaryKey, DBTypes dataType)
{
return m_Server.Retrieve( primaryKey, dataType );
}

Thanks for your reply

Niraj