View Compilation Error

571924_0_0_4755.cpp
571924_0_0_4755.cpp(17) : error C2475: “std::basic_string<_Elem,_Traits,_Ax>::length” : 构造一个指向成员的指针需要显式使用 address-of 运算符('&')和限定名
        with
        [
            _Elem=char,
            _Traits=std::char_traits<char>,
            _Ax=std::allocator<char>
        ]
571924_0_0_4755.cpp(17) : error C2475: “std::basic_string<_Elem,_Traits,_Ax>::length” : 构造一个指向成员的指针需要显式使用 address-of 运算符('&')和限定名
        with
        [
            _Elem=char,
            _Traits=std::char_traits<char>,
            _Ax=std::allocator<char>
        ]
571924_0_0_4755.cpp(17) : error C2446: “==” : 没有从“int”到“std::basic_string<_Elem,_Traits,_Ax>::size_type (__thiscall std::basic_string<_Elem,_Traits,_Ax>::* )(void) const”的转换
        with
        [
            _Elem=char,
            _Traits=std::char_traits<char>,
            _Ax=std::allocator<char>
        ]
        没有从整数值到指向成员的指针值的转换
571924_0_0_4755.cpp(17) : error C2040: “==” : “std::basic_string<_Elem,_Traits,_Ax>::size_type (__thiscall std::basic_string<_Elem,_Traits,_Ax>::* )(void) const”与“int”的间接寻址级别不同
        with
        [
            _Elem=char,
            _Traits=std::char_traits<char>,
            _Ax=std::allocator<char>
        ]