if(this._IsExistChildForm("ChildForm"))

{

return;

}

ChildForm childForm= new ChildForm();

childForm.MdiParent = this;

childForm.Name = "ChildForm";

childForm.Show();

/// <summary>

/// 判断是否含有该子窗体

/// </summary>

/// <param name="_ChildFormName">子窗体名称</param>

/// <returns>bool</returns>

private bool _IsExistChildForm(string _ChildFormName)

{

foreach(Form form in this.MdiChildren)

{

if(string.Compare(form.Name, _ChildFormName, true) == 0)

{

form.BringToFront();

return true;

}

}

return false;

}