Close the second child form if one form is already open

Question

I have created windows application in which there is a parent form with many child forms. Now what I want to do is, Close the second form if first form is opened. I have menustrip control, that is disabled once any form is opened and enabled if form is closed. Now I have added shortcut keys in menu strip for opening the forms. By using the shortcut I open the first form, then again by using shortcut, the second form is opened and the first form is closed instead of second form.

 The code I wrote :-

 

void MDIParent1_MdiChildActivate(object sender, EventArgs e)

{

      if (this.MdiChildren.Count() > 1)

         {

                     foreach (Form childForm in this.MdiChildren)

                     {                                                     

                                 if (childForm != this.ActiveMdiChild)

                                 {

                                          childForm.Close();

                                          return;

                                  }

                     }

            }

}

 

 

Thanks in Advance !!!!