title: how to call MdiChild from MDIParent form
body: <p>I create a new MdiChild from MainForm using this method:</p>
  
  <pre><code>AdminLogInForm adminForm;
   private void LogInAsAdminMenuItem_Click(object sender, EventArgs e)
      {
          if (adminForm == null)
          {
              adminForm = new AdminLogInForm();
              adminForm.MdiParent = this;
              adminForm.Show();
              adminForm.Dock = DockStyle.Fill;
              adminForm.BringToFront();
              LogInAsAdminMenuItem.Enabled = false;              
          }
          else
          {
              adminForm.Activate();
              adminForm.BringToFront();
          }
      }
  </code></pre>
  
  <p>Why when i close my child, using in chld form "this.close()" using that method i cant open it anymore?</p>
  
  <p>there i call close();</p>
  
  <pre><code>        private void cancelLogInButton_Click(object sender, EventArgs e)
      {
          this.MdiParent.Activate();            
          if(this.MdiParent!=null)
          ((MainForm)this.MdiParent).LogInAsAdminMenuItem.Enabled = true;
          this.Close();
      }
  </code></pre>
  
  <p>by the way to make work that I asked before I hed to plase  this.Close(); after all statements .</p>