Create Login Form on C#

Question

Hi Guys

This is the code i have used on C# to create a login form and it always prompts me with "Invalid username or password" even though my database holds the correct username and password. Please help???

private void button1_Click(object sender, EventArgs e)
        {
            string username = textBox1.Text;
            string password = textBox2.Text;

            if (ValidateUserNamePassword(username, password))
            {
                MessageBox.Show("Login successful");

            }
            else
            {
                MessageBox.Show("Invalid user name or password");
                return;
            }
        }

        public bool ValidateUserNamePassword(string username, string password)
        {

            MySqlConnection cn = new MySqlConnection(@"SERVER=localhost;" + "DATABASE=clientmanagement;" + "UID=root;" + "PASSWORD=qwerty;");
            {
                MySqlCommand cmd = new MySqlCommand();
                cmd.Connection = cn;
                cmd.CommandType = CommandType.StoredProcedure;
                cmd.CommandText = "tsp_GetUserNameAndPassword";

                MySqlParameterCollection sqlParams = cmd.Parameters;
                sqlParams.AddWithValue("@UserName", username);
                sqlParams.AddWithValue("@Password", password);

                cn.Open();
                MySqlDataReader dr = cmd.ExecuteReader(CommandBehavior.SingleRow);
                if (dr.Read())
                {
                    // this will return true if a row matching the username and password is found.
                    // this means that the user's input is valid
                    return true;
                }
                else
                {
                    return false;
                }

                dr.Close();
                cn.Close();

            }
        }
        private void button2_Click(object sender, EventArgs e)
        {
            Application.Exit();
        }
    }
}

Nidhi Shah · Answer

SqlConnection con.Open(); cmd.ExecuteNonQuery(); da.Fill(ds); con.Close(); con = new SqlConnection (strConn); string strCmd = select UserName Password from Login where UserName=' + txtUserName.Text + ' and Password =' + txtPassword.Text + ' ; SqlCommand cmd = new SqlCommand (strCmd con); SqlDataAdapter da = new SqlDataAdapter (strCmd con); DataSet ds = new DataSet (); MessageBox .Show( Login successful  Success  MessageBoxButtons .OK MessageBoxIcon .Information);

Suthish Nair · Answer

Are you sure your query returns SingleRow only? try with SingleResult. Run the sql statement from procedure inside your editor window to check the output. Put a breakpoint and check the value getting here (dr.Read()). Also take care of upper/lower case of characters.

piyush sardhara · Answer

nidhi write code propely

Suthish Nair · Answer

Vulpes is right... try... CREATE DEFINER=`root`@`%` PROCEDURE tsp_GetUserNameAndPassword( @username varchar(max) @Password varchar(max)) SELECT username password FROM login WHERE lower(username) = lower(@UserName) AND password = @Password; Another thing do you have access to DB? try...

Vulpes · Answer

I don't use MySql but you're not defining your two parameters in an IN clause within the brackets after the procedure name. Also there's no END though I assume this is because you've only posted an extract. Apart from that you are returning a row rather than a single value so your code should work.

Kamil Zahid · Answer

This is what i have in mysql editor for the procedure is it OK? CREATE DEFINER=`root`@`localhost` PROCEDURE `tsp_GetUserNameAndPassword`() BEGIN SELECT username password FROM login WHERE username = @UserName AND password = @Password;

Vulpes · Answer

If it is returning a single value (a boolean say) rather than a whole row then ExecuteScalar() should also work: bool result = (bool)cmd.ExecuteScalar();