如何防止包含两次头文件?问题是我包括了在MyClass.h中然后我将MyClass.h包含在许多文件中,因此它包含多次并发生重定义错误.怎么预防?
我正在使用#pragma而不是包含警卫,我想这很好.
MyClass.h:
// MyClass.h
#pragma once
#include <winsock2.h>
class MyClass
{
// methods
public:
MyClass(unsigned short port);
virtual ~MyClass(void);
};
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编辑:我得到的错误很少
c:\program files\microsoft sdks\windows\v6.0a\include\ws2def.h(91) : warning C4005: 'AF_IPX' : macro redefinition
c:\program files\microsoft sdks\windows\v6.0a\include\winsock.h(460) : see previous definition of 'AF_IPX'
c:\program files\microsoft sdks\windows\v6.0a\include\ws2def.h(124) : warning C4005: 'AF_MAX' : macro redefinition
c:\program files\microsoft sdks\windows\v6.0a\include\winsock.h(479) : see previous definition of 'AF_MAX'
c:\program files\microsoft sdks\windows\v6.0a\include\ws2def.h(163) : warning C4005: 'SO_DONTLINGER' : macro redefinition
c:\program files\microsoft sdks\windows\v6.0a\include\winsock.h(402) : …Run Code Online (Sandbox Code Playgroud)