SYSK 102: Unexpected Behavior in Generics

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Consider the following: 

 

static public class MyClass

{

    static public void Method<T>(T x)

    {

        . . .

        MethodX(x);

        . . .

    }

    static private void MethodX(float x)

    {

        System.Diagnostics.Debug.WriteLine("Float");

    }

    static private void MethodX(object x)

    {

        System.Diagnostics.Debug.WriteLine("Object");

    }

}

. . .

float x = 1f;

MyClass.Method<float>(x);

. . .

 

What method will be called – MethodX(float x) or MethodX(object x)?

 

As it turns out, it’ll always invoke the MethodX(object x)!  The only way I found to get the “expected” behavior is to do the explicit cast – MethodX((float) x), which requires the knowledge of passed in data types and an ugly switch statement…