C# Error CS0756 – A partial method may not have multiple defining declarations

C# Error

CS0756 – A partial method may not have multiple defining declarations

Reason for the Error & Solution

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

1. 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;  
        }  
    }