private void loginButton_Click(object sender, EventArgs e) { string id = idTextbox.Text; string pw = pwTextbox.Text; SocketManager.sendData(id + ',' + pw); string receive = SocketManager.getData(); if (receive == "Success") { this.DialogResult = DialogResult.OK; } else { MessageBox.Show("다시 확인해 주세요.", "알림"); ActiveControl = idTextbox; idTextbox.Text = ""; pwTextbox.Text = ""; } }