Will VC++ 2005 implement switch with case int::typeid in the final release?

[nobody]

With Visual C++ 2005 beta 2, I get the below compling error for the
following code. I think this error is not acceptable to me because
int::typeid is a constant and is known to compiler when compiling. Will VC++
2005 implement switch with case int::typeid in the final release?

error C2450: switch expression of type 'System::Type ^' is illegal

1> No user-defined-conversion operator available, or

1> Integral expression required

1>.\sproadapter.cpp(271) : error C2051: case expression not constant



Type ^t = obData->GetType();

switch (t)

{

case int::typeid:

break;

default:

break;

}

 

[Lloyd Dupont]

I believe that C++ doesn't care about constantness, it just takes only int
(or type with implicit cast to int) argument.

 

[Carl Daniel [VC++ MVP]]

With Visual C++ 2005 beta 2, I get the below compling error for the
following code. I think this error is not acceptable to me because
int::typeid is a constant and is known to compiler when compiling.
Will VC++ 2005 implement switch with case int::typeid in the final
release?

No.

System::Type is not an integer type and therefore cannot be used as the type
of a switch/case regardless of real or apparent const-ness.

-cd

 

[nobody]

Consider the following code:

Type ^t = obData->GetType();

if(t == int::typeid)

{

//do something

}

else if(t == __int64::typeid)

{

Type ^t = obData->GetType();

}

else if(t == double::typeid)

{

Type ^t = obData->GetType();

}

else if(t == float::typeid)

{

Type ^t = obData->GetType();

}

else

{

}



If I can use switch, it will much better. Do you know any method to use
switch?

 

[Tomas Restrepo \(MVP\)]

Consider the following code:

If I can use switch, it will much better. Do you know any method to use
switch?

No, you can't. Depending on what you're doing you might be able to implement
a table driven approach, but that's about it.

 

[Brandon Bray [MSFT]]

If I can use switch, it will much better. Do you know any method to use
switch?

While everyone else is correct that this is not supported by the C++
language, you can request that it be supported (see link to feedback below).
This request is very similar to another feature which we do not support --
switch on strings. C# supports switch on strings. The code generated in both
your case and the string case would effectively be a series of if-then-else
statements.