Compiler Error CS0756

A partial method may not have multiple defining declarations.

The defining declaration of a partial method is the part that specifies the method signature, but not the implementation (method body). A partial method must have exactly one defining declaration for each unique signature. Each overloaded version of a partial method must have its own defining declaration.

To correct this error

  • Remove all except one defining declaration for the partial method.

Example

// cs0756.cs
using System;

    public partial class C
    {
        partial void Part();
        partial void Part(); // CS0756
        public static int Main()
        {
            return 1;
        }
    }

See Also

Reference

Partial Classes and Methods (C# Programming Guide)