C#中避免相同MDI子窗口重复打开的方法

   1: // 是否已经打开了？（用循环来判断） 
   2: foreach (Form childrenForm in this.MdiChildren)
   3: {
   4:     //检测是不是当前子窗体名称
   5:     if (childrenForm.Name == "FormExaminee")
   6:     {
   7:         //是的话就是把他显示
   8:         childrenForm.Visible = true;
   9:         //并激活该窗体
   10:         childrenForm.Activate();
   11:         childrenForm.WindowState = FormWindowState.Maximized;
   12:         return;
   13:     }
   14: }
   15:
   16: //如果没有打开，则新建窗体
   17: FormChild.FormExaminee formExaminee = new FormChild.FormExaminee();
   18: formExaminee.MdiParent = this;
   19: formExaminee.WindowState = FormWindowState.Maximized;
   20: formExaminee.Show();