private void button4_Click(object sender, EventArgs e)
{
HeThong form1 = new HeThong();
form1.Show();
this.Hide();
}
private void quayLạiToolStripMenuItem_Click(object sender, EventArgs e)
{
HeThong form2 = new HeThong();
form2.Show();
this.Hide();
}
private void btn_login_Click(object sender, EventArgs e)
{
SqlConnection con = new SqlConnection(conn);
con.Open();
SqlCommand cmd = new SqlCommand("select count(*) from NguoiDung where Taikhoan = '" + txt_taikhoan.Text + "'and Matkhau = '" + txt_matkhau.Text + "'", con);
int temp = Convert.ToInt32(cmd.ExecuteScalar().ToString());
con.Close();
if (temp == 1)
{
MessageBox.Show("Đăng nhập thành công!");
HeThong form1 = new HeThong();
form1.Show();
this.Hide();
}
else
{
MessageBox.Show("Sai tên tài khoản hoặc mật khẩu!");
}
}