先粗略记一下。。。。

对同一个操作符同时实现成员函数重载和友元重载时，优先调用成员重载，当不存在成员重载时调用友元重载

1 #include "stdafx.h" 2  3 class CTest { 4 public: 5     CTest(int nValue) : nValue_(nValue) {} 6  7     friend bool operator ==(const CTest& t1, const CTest& t2) { 8         return t1.nValue_ == t2.nValue_; 9     }10 11     bool operator == (const CTest& t) {12         return nValue_ == t.nValue_;13     }14 15 private:16     int nValue_;17 };18 19 int _tmain(int argc, _TCHAR* argv[])20 {21     CTest t1(1);22     CTest t2(2);23     bool bSame = t1 == t2;24     bSame = t1.operator==(t2);25     bSame = operator == (t1, t2);26     return 0;27 }