我先创建了dlg2对话框,接着创建了它对应的对话框类class dlg2,利用类向导添加消息响应函数之后,准备实现简单功能,但在编译时出现如下错误:E:\Microsoft Visual Studio\MyProjects\geliang\geliangDlg.cpp(175) : error C2065: 'dlg2' : undeclared identifierE:\Microsoft Visual Studio\MyProjects\geliang\geliangDlg.cpp(175) : error C2146: syntax error : missing ';' before identifier 'test'E:\Microsoft Visual Studio\MyProjects\geliang\geliangDlg.cpp(175) : error C2065: 'test' : undeclared identifierE:\Microsoft Visual Studio\MyProjects\geliang\geliangDlg.cpp(176) : error C2228: left of '.DoModal' must have class/struct/union typedlg2.cppGenerating Code...Error executing cl.exe.geliang.exe - 4 error(s), 0 warning(s) 其中消息响应函数如下:void CGeliangDlg::OnOK() { // TODO: Add extra validation here dlg2 test; int result=test.DoModal(); if (result==IDOK) { AfxMessageBox("单击OK按钮"); } else { AfxMessageBox("单击cancle按钮"); } CDialog::OnOK();}请问错在哪了?为什么会出现这些错误?