MFC创建读取txt文档Dialog

void COpenTxt::OnFileopen() //COpenTxt为新建Dialog类，OnFileopen为打开文档的按钮
{


CFileDialog fileDlg(TRUE); 
if(fileDlg.DoModal() == IDOK) 
{ 
CString str; 
CFile f; 
f.Open(fileDlg.GetFileName(),CFile::modeReadWrite); 
f.Read(str.GetBuffer(f.GetLength()),f.GetLength()); 
f.Close(); 
//MessageBox("打开成功!","提示",MB_OK);
GetDlgItem( IDC_SEND )->SetWindowText( str); //IDC_SEND为编辑文本框，输出文本
} 

}