C++ 操作符=的重载

可以把赋值操作符认为是一个析构函数和一个复制构造函数的组合

 

Spreadsheet& Spreadsheet::operator =(const Spreadsheet& rhs){    int i, j;    if (this == &rhs)   //判断赋值号两边是否相等    {        return (*this);    }        for (i = 0; i < mWidth; i++)  //首先释放旧的内存    {        delete[] mCells[i];    }    delete[] mCells;        mWidth = src.mWidth;    mHeight = src.mHeight;    mCells = new SpreadsheetCell* [mWidth];    for (i = 0; i < mWidth; i++)      //然后创建新的内存    {        mCells[i] = new SpreadsheetCell [mHeight];    }    for (i = 0; i < mWidth; i++)    {        for(j = 0; j < mHeight; j++)        {            mCells[i][j] = src.mCells[i][j];        }    }}