public static frmClientAccountAdd GetInstance()
 {
     if (frmCAccountAdd == null)
     {
         frmCAccountAdd = new frmClientAccountAdd();
     }
     return(frmCAccountAdd);
 }
        private void button1_Click(object sender, EventArgs e)
        {
            frmClientAccountAdd fm = frmClientAccountAdd.GetInstance();

            fm.ShowDialog();
        }
        private void button1_Click(object sender, EventArgs e)
        {
            frmClientAccountAdd fm = new frmClientAccountAdd();

            fm.ShowDialog();
        }