Question

vc6.0老是提示error C2065: 'r' : undeclared identifier

if(MenuID==3||MenuID==4&&PressNum==1) { pDC.SelectStockObject(NULL_BRUSH);//画空心圆 if(mPointOld!=point) { r=(int)sqrt((mPointOrign.x-mPointOld.x)*(mPointOrign.x-mPointOld.x)+(mPointOrign.y-mPointOld.y)*(mPointOrign.y-mPointOld.y)); pDC.Ellipse(mPointOrign.x-r,mPointOrign.y-r,mPointOrign.x+r,mPointOrign.y+r);//擦旧圆 r=(int)sqrt((mPointOrign.x-point.x)*(mPointOrign.x-point.x)+(mPointOrign.y-point.y)*(mPointOrign.y-point.y)); pDC.Ellipse(mPointOrign.x-r,mPointOrign.y-r,mPointOrign.x+r,mPointOrign.y+r);//画新圆 mPointOld=point; } } CView::OnMouseMove(nFlags, point); } void CMy200732590103View::OnDrawDdaline() { // TODO: Add your command handler code here PressNum=0;MenuID=1;

若以下回答无法解决问题，邀请你更新回答

Answer 1

变量r未定义。。。 声明一下r吧