关于m_ptStart未声名问题，具体代码如下

Question

void CWrite2View::OnLButtonDown(UINT nFlags, CPoint point)
{
// TODO: Add your message handler code here and/or call default
m_ptStart=point;
m_ptEnd=point;
SetCapture();
m_isDragging=true;
CListView::OnLButtonDown(nFlags, point);
}
错误信息：
C:\Users\john\Desktop\VChh\MyProjects\Write2\Write2View.cpp(111) : error C2065: 'm_ptStart' : undeclared identifier
C:\Users\john\Desktop\VChh\MyProjects\Write2\Write2View.cpp(111) : error C2679: binary '=' : no operator defined which takes a right-hand operand of type 'class CPoint' (or there is no acceptable conversion)
C:\Users\john\Desktop\VChh\MyProjects\Write2\Write2View.cpp(112) : error C2065: 'm_ptEnd' : undeclared identifier
C:\Users\john\Desktop\VChh\MyProjects\Write2\Write2View.cpp(112) : error C2679: binary '=' : no operator defined which takes a right-hand operand of type 'class CPoint' (or there is no acceptable conversion)
C:\Users\john\Desktop\VChh\MyProjects\Write2\Write2View.cpp(114) : error C2065: 'm_isDragging' : undeclared identifier
C:\Users\john\Desktop\VChh\MyProjects\Write2\Write2View.cpp(131) : error C2679: binary '=' : no operator defined which takes a right-hand operand of type 'class CPoint' (or there is no acceptable conversion)
执行 cl.exe 时出错.

Answer 1

问你啊，这个变量定义了么，在哪里