Visual Studio2008编译错误error C2259 cannot instantiate abstract class 经过检查，发现源代码中确实已经派生了虚函数，派生的虚函数源文件也正常编译。 最后在微软的官方网站上找到了答案（可能只是error C2259其中一种可能的原因，供参考）： This behavior is by design with VS 2005. The root cause is because wchar_t is a different type than unsigned short though in prior versions of Visual C++, the compiler considered them to be the same type. In this sample code, the type library uses [...]

环境：  Visual Studio 2008 C++ 编译错误： error LNK2005: _DllMain@12 already defined … The CRT libraries use weak external linkage for the new, delete, and DllMain functions. The MFC libraries also contain new, delete, and DllMain functions. These functions require the MFC libraries to be linked before the CRT library is linked. 微软的支持文档指出，MFC库的链接必须在CRT库之前，而解决方法有2种： 1. 强制连接器以正确的顺序链接，具体方法见下面的微软链接。 2. [...]