Winform避免相同MDI子窗口重复打开的方法

Winform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();