新建和打开 Form3 childForm=new Form3(); childForm.Text="新建文档.txt*"; childForm.MdiParent= 设置父窗体为当前窗体 childForm.Show(); openFileDialog1.Filter="文本文档*.txt所有文档*.*"； DialogResult dr=openFileDialog1.ShowDialog(); if(dr =DialogResult.OK) { Form3 childForm new Form3(openFileDialog1 .FileName); childForm.MdiParent=this; 调用重载的构造函数 childForm.Show(); 1616 新建和打开 Form3 childForm = new Form3(); childForm.Text = "新建文档.txt*"; childForm.MdiParent = this; childForm.Show(); 设置父窗体为当前窗体 openFileDialog1.Filter = "文本文档|*.txt|所有文档|*.*"; DialogResult dr=openFileDialog1.ShowDialog(); if (dr == DialogResult.OK) { Form3 childForm = new Form3(openFileDialog1 .FileName); childForm.MdiParent = this; childForm.Show( ); } 调用重载的构造函数