If-else vs switch - declaring inner variables (a philosophical question)

[David Burstin]

Hi folks,

I was wondering if someone could explain the logic of the following in c#:

Using If-Else:

            if (x == 7)
            {
                string foo = "a";
            }
            else
            {
                string foo = "b";  // No problem declaring the string here
            }

Using Switch:
            switch (x)
            {
                case 7:
                    string foo = "a";
                    break;
                default:
                    string foo = "b"; // Compiler not happy because foo
already declared within the switch scope
                    break;
            }

I understand that the scope for the second example is the entire switch
statement, but why does that need to be the case (pardon the pun)? Is it
just because of the ability to fall through from one case statement to the
next (by omitting the break)?

Just as a comparison, the compiler has no problem with the following in VB:

        Select Case x
            Case 7
                Dim foo As String = "a"
            Case Else
                Dim foo As String = "b"
        End Select