Compiler Error CS0428
Updated: August 2009
Cannot convert method group 'Identifier' to non-delegate type 'type'. Did you intend to invoke the method?
This error occurs when converting a method group to a non-delegate type, or attempting to invoke a method without using parentheses.
The following sample generates CS0428:
// CS0428.cs namespace ConsoleApplication1 { class Program { delegate int Del1(); delegate object Del2(); static void Main(string[] args) { ExampleClass ec = new ExampleClass(); // The following assignment statement causes compiler error CS0428. // It attempts to assign the address of Method1 to an integer variable. // You can only assign the address to an appropriate delegate type. int i = ec.Method1; // Del1 is a delegate type that is appropriate for a method like // Method1 that returns an int. The following assignment statement // does not cause an error. Del1 d1 = ec.Method1; // You can invoke Method1 and assign the int that is returned to // integer variable i. i = ec.Method1(); // The following assignment statement causes compiler error CS0428. // It attempts to assign the address of Method2 to an instance of // ExampleClass. You can only assign the address to a delegate type. ec = ExampleClass.Method2; // Del2 is a delegate type that is appropriate for a method like // Method2 that returns an instance of a class. The following assignment // statement does not cause an error. Del2 d2 = ExampleClass.Method2; // Similarly, you can invoke Method2 and assign the result returned to ec. ec = ExampleClass.Method2(); } } public class ExampleClass { public int Method1() { return 1; } public static ExampleClass Method2() { return null; } } }
