运算符这个函数的参数太多了？ [英] Operator(s) too many parameters for this function?

问题描述

做我自己的字符串类（即显然为家庭作业），并得到奇怪的语法错误我的两个运算符。我的平等和添加运算符声称我有太多的参数（即在我的.h文件中），但是声明该方法甚至不属于我的.cpp文件中的类！

Made my own string class (i.e. for homework obviously) and am getting odd syntax errors on two of my operators. My equality and add operators claim I have too many parameters (i.e. in my .h file), but then claim the method does not even belong to the class in my .cpp file!

我甚至让平等运算符成为朋友，但是intellisense仍然给我相同的错误消息。

I even made the equality operator a friend, but the intellisense still gives me the same error messages.

有人知道我在做什么错误

Does anyone know what I am doing wrong??

friend bool operator==(String const & left, String const & right);

string.h

bool operator==(String const & left, String const & right);
String const operator+(String const & lhs, String const & rhs);

string.cpp

bool String::operator==(String const & left, String const &right)
{
    return !strcmp(left.mStr, right.mStr);
}

String const String::operator+(String const & lhs, String const & rhs)
{
    //Find the length of the left and right hand sides of the add operator
    int lengthLhs = strlen(lhs.mStr);
    int lengthRhs = strlen(rhs.mStr);

    //Allocate space for the left and right hand sides (i.e. plus the null)
    char * buffer = new char[lhs.mStr + rhs.mStr + 1];

    //Copy left hand side into buffer
    strcpy(buffer, lhs.mStr);

    //Concatenate right hand side into buffer
    strcat(buffer, rhs.mStr);

    //Create new string
    String newString(buffer);

    //Delete buffer
    delete [] buffer;

    return newString;
}

推荐答案

c $ c> operator == 以外的类：

You need to define operator== outside the class:

bool String::operator==(String const & left, String const &right)
     ^^^^^^^^ REMOVE THIS

如果 operator + 也是一个朋友，它也需要定义为一个自由函数（即类外）。

If operator+ is also a friend, it too needs to be defined as a free function (i.e. outside the class).

这篇关于运算符这个函数的参数太多了？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！