Signing a COM Interop Method with ByRef

Question

I have a C # program that calls a COM library that has a method called testwith two parameters: the first parameter is passed ByVal, the second is passed ByRef.

This is what the COM library does:

Public Sub test(ByVal a As String, ByRef b As String)
    a = "a"
    b = "b"
End Sub

This is what the C # program does:

test.Class1 x = new test.Class1();
            string a = "1";
            string b = "2";
            x.test(a, ref b);

I notice that if I delete the keyword ref, the compiler does not advise me to skip the keyword refand pass the parameter ByVal. This can be a big problem if I missed a keyword ref, because I can’t notice it until I know what it wants ref. Do you know why the compiler demonstrates this behavior?

Answer 1

COM- # 4 . , ref. # 4 , Office. Office api , VB, ByRef . , VBA. , api , ByRef, .

, . . -, . , :)