Question

Well im here because i have a problem. i have code that was created a while ago. my code is working properly when i a user type the correct username and password. so my problem is when a user insert wrong username and password error message wont show. Here is my code:

MyDs.Clear();
MyDa.SelectCommand = Conn.CreateCommand();
MyDa.SelectCommand.CommandText = 
    "select * from PersonalName where Firstname=@first and Lastname=@last";
MyDa.SelectCommand.CommandType = CommandType.Text;
MyDa.SelectCommand.Parameters.Add("@first", DbType.String, 25, "Firstname").Value = textbox_Username.Text;
MyDa.SelectCommand.Parameters.Add("@last", DbType.String, 25, "Lastname").Value = textbox_Password.Text;

MyDa.Fill(MyDs);
foreach (DataRow item in MyDs.Tables[0].Rows)
{
    if (textbox_Username.Text != item[1].ToString() || textbox_Password.Text != item[3].ToString())
    {
        MessageBox.Show("not connected");
    }
    else
    {
        MessageBox.Show("Connected");
    }
}

Anyone can tell me what is the problem with this code?

Answer 1

Your dataset will be empty if they put in the wrong username. This will be closer to what you want:

if (MyDs.Tables[0].Rows.Count > 0)
{
    // you don't need to check username, the SQL query took care of that

    if (textbox_Password.Text == item[3].ToString())
        MessageBox.Show("Connected.");
    else
        MessageBox.Show("Failed."); // wrong password
}
else
    MessageBox.Show("Failed."); // no such user