private void btnLogin_Click_1(object sender, EventArgs e) { if (b_user.Call_Get_accuracy(txttk.Text, txtmk.Text)) { frm_Main frmmain = new frm_Main(); frmmain.Get_name_user(txttk.Text); frmmain.FormClosed += new FormClosedEventHandler(mainForm_FormClosed); frmmain.Show(); this.Hide(); } else { MessageBox.Show("Failure"); } }