public static FrmOrder GetSingleton()
{
if (frm == null || frm.IsDisposed)
{
frm = new FrmOrder();
}
return(frm);
}
private void tsmiOrder_Click(object sender, EventArgs e)
{
FrmOrder frm = FrmOrder.GetSingleton();
frm.MdiParent = this;
frm.Show();
frm.Activate();
}