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int64 and long woes...

OK, I know that in C# long is simply a shortcut to int64. But I am looking to make an app that is COM visible. The other side of the application expects to see a type library with this kind of interface:

...
        [id(0x60020002), propget]
        HRESULT gParentWnd([out, retval] long* pRetVal);
        [id(0x60020002), propput]
        HRESULT gParentWnd([in] long pRetVal);
...

The closest I can get in C# is this:

        [id(0x60020002), propget]
        HRESULT gParentWnd([out, retval] int64* pRetVal);
        [id(0x60020002), propput]
        HRESULT gParentWnd([in] int64 pRetVal);

See how the longs are no longer longs, they are int64. This is a problem on the other end where they are looking for signatures that contain the long data type. I can't seem to get VC# to output long as the data type. Anyone know of a workaround?

Steve Luke Thursday, October 08, 2009 10:01 PM

You're almost right.

In C#, long is an Int64.

However, in IDL , long is a 32bit integer value.

To make this work, setup your C# project with int , not long . C#'s int matches the long type in IDL (and C++, btw).

Reed Copsey, Jr. - http://reedcopsey.com