Check out example codes for "c# delegate return value invoke". It will help you in understanding the concepts better.

Code Example 1

public void TestIndividualInvokesRetVal( )
{
    MultiInvoke MI1 = new MultiInvoke(TestInvoke.Method1);
    MultiInvoke MI2 = new MultiInvoke(TestInvoke.Method2);
    MultiInvoke MI3 = new MultiInvoke(TestInvoke.Method3);

    MultiInvoke All = MI1 + MI2 + MI3;

    int retVal = -1;

    Console.WriteLine("Invoke individually (Obtain each return value):");
    foreach (MultiInvoke individualMI in All.GetInvocationList( ))
    {
        retVal = individualMI( );
        Console.WriteLine("\tOutput: " + retVal);
    }
}

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