string函数_C++[06] string成员函数之删除函数erase

介绍一下删除函数erase，老方法，新建cpp文件，并找到string的erase成员函数，可以看到，erase有3个重载函数

右键转到定义，可以查看erase的源码

_Myt&erase(size_type_P0=0,size_type_M=npos){if(_Len _Split(); if(_Len-_P0 if (0 < _M) { _Tr::move(_Ptr+_P0,_Ptr+_P0+_M,_Len-_P0-_M);size_type _N = _Len - _M; if(_Grow(_N))_Eos(_N);} return (*this); }iterator erase(iterator _P){ size_t _M = _Pdif(_P, begin()); erase(_M, 1);return(_Psum(_Ptr,_M));}iterator erase(iterator _F, iterator _L){ size_t _M = _Pdif(_F, begin()); erase(_M, _Pdif(_L, _F)); return (_Psum(_Ptr, _M)); }

可以看到，erase重载函数之间又有相互调用，下面看例子

string str = "Hello_World_Welcome";cout << "str -> " << str << endl;cout << "str.begin() -> " << str.begin() << "\tstr.end()-1 -> " << str.end()-1 << endl << endl ;cout << "iterator erase(iterator first, iterator last)" << endl;string::iterator iter = str.begin();iter = str.erase(str.begin()+5, str.end()-9);cout << "after str.erase(str.begin()+5, str.end()-9) -> " << str << endl << "return iter -> " << *iter << endl;str = "Hello_World_Welcome";iter = str.erase(str.begin()+3, str.end()-8);cout << "after str.erase(str.begin()+3, str.end()-8) -> " << str << endl << "return iter -> " << *iter << endl;cout << "############################" << endl << endl;cout << "string& erase(unsigned int strart_id, unsigned int end_id)" << endl;str = "Hello_World_Welcome";cout << "str.erase(6, 10)->" << str.erase(6, 10) << endl;str = "Hello_World_Welcome";cout << "str.erase(8, 13)->" << str.erase(8, 13) << endl;cout << "############################" << endl << endl;str = "Hello_World_Welcome";iter = str.erase(str.begin()+5);cout << "after str.erase(str.begin()+5) -> " << str << endl << "return iter -> " << *iter << endl;str = "Hello_World_Welcome";iter = str.erase(str.end()-10);cout << "after str.erase(str.end()-10) -> " << str << endl << "return iter -> " << *iter << endl;cout << "############################" << endl << endl;

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