C++ include and import difference

c++ visual-c++ gcc import include
Marius picture Marius · Oct 5, 2008 · Viewed 61k times · Source

What is the difference between #include and #import in C++?

Answer

Brian R. Bondy picture Brian R. Bondy · Oct 5, 2008

Import in VC++: #import is for type libraries or .tlbs (COM stuff).

The content of the type library is converted into C++ classes, mostly describing the COM interfaces for you automatically, and then it is included into your file.

The #import directive was introduced by Microsoft as an extension to the C++ language. You can read about it at this MSDN article.

The #import directive is also used with .NET / CLI stuff.

Import in gcc: The import in gcc is different from the import in VC++. It is a simple way to include a header at most once only. (In VC++ and GCC you can do this via #pragma once as well)

The #import directive was officially undeprecated by the gcc team in version 3.4 and works fine 99% of the time in all previous versions of gcc which support

Include: #include is for mostly header files, but to prepend the content to your current file. #include is part of the C++ standard. You can read about it at this MSDN article.

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