private void btnDangNhap_Click(object sender, EventArgs e)
{
//Có 2 TextBox txtTenDangNhap và txtMatKhau, có 1 button btnDangNhap
//CSDL có bảng tblDangNhap có field : ten_dn, mat_khau, ....
string strtendn=txtTenDangNhap.Text;
strtendn=strtendn.ToLower();
string strmatkhau=txtMatKhau.Text;
string sqlselect = "select * from tblDangNhap where ten_dn='"+ strtendn + "' and mat_khau='" + strmatkhau + "'";
string strconn = @"chuoi_ket_noi";
SqlConnection connect=new SqlConnection (strconn);
SqlDataAdapter da = new SqlDataAdapter(sqlselect,connect);
DataTable dt = new DataTable();
da.Fill(dt);
if (dt.Rows.Count != 0)
MessageBox.Show("Dang nhap thanh cong!","Thong bao", MessageBoxButtons.OK, MessageBoxIcon.Information);
else
MessageBox.Show("Dang nhap ko thanh cong!", "Thong bao", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
Tiêu đề: Cho minh hoi ti 
Fri Sep 09, 2011 9:15 am
