How do I avoid 'call is ambiguous...' errror when writing static and non-static methods in C# ?

Question

I have a number of classes that represents business transaction calls: executing appropriate stored procedures.

Now the looks like this:

public static class Request
{
    public static void Approve(..) {
        using(connection) {
            command.Text = "EXEC [Approve] ,,"]
            command.ExecuteNonQuery();
        }
    }
}

And I want to make them more thread-safe:

public class Request {
    public static void Approve(..) {
        new Request().Approve(..);
    }

    internal void Approve(..) {
        using(connection) {
            command.Text = "EXEC [Approve] ,,"]
            command.ExecuteNonQuery();
        }
    }
}

But getting next error message:

The call is ambiguous between the following methods or properties: 'MyNamespace.Request.Approve(..)' and 'MyNamespace.Request.Approve(..)'

How can I force, mark that I'm calling non-static, instance method from static?

Or I cannot do that without renaming one of the methods? Or moving static method to another class, etc

Answer 1

If you're making a call from an instance (e.g. requestVar.Approve()), then no, you have to rename it. The static can be called by using Request.Approve() however.

Answer 2

C# allows does not allow static methods to be called through instance references. As such - the methods must either be named differently or use argument overloading to differentiate static methods from instance methods.

In your example, since the Approve() method is internal, renaming it is probably your easiest option.

As to marking that a method is static ... I (personally) think the name is a perfectly good means to differentiate the two - why invent something more complicated.