Question

When ‘login’ button is clicked I would like to iterate through a column in a table and check if a match occurs. How would I go about doing this?
I have connected through to a database and I’m reading from database and writing to database fine. I am not sure how I would iterate through a database.

P.S I’m new to both c# and visual studios. I am not having much trouble with C#, since I come over from Java however I’m struggling to get into grips with Visual studios.

Answer 1

This is simple you’ll see.

            SqlConnection myConnection = new SqlConnection(@"Server = (Local); Integrated Security = True;" + "Database = insertDataBaseName"); // Assuming (Local)
            myConnection.Open();
            SqlCommand myCommand = myConnection.CreateCommand();
            myCommand.CommandText = ("SELECT UserName, Password,from Login"); // Where Login is your table . UserName and Password Columns
            SqlDataReader myReader = myCommand.ExecuteReader();
            bool login = false;

            while (myReader.Read())
            {
                if (userNameBox.Text.CompareTo(myReader["UserName"].ToString()) == 0 && passwordBox.Text.CompareTo(myReader["Password"].ToString()) == 0) // A little messy but does the job to compare your infos assuming your using a textbox for username and password
                {
                    login = true;
                }
            }

            if (login)
            {
                      //Your're in.
            }

            else
            {
                MessageBox.Show("Invalid UserName or Password", "Access Denied"); // Error message
            }

                 myReader.Close(); 
                 myConnection.Close(); // Just close everything

Hope this helps.
Dont hesitate if you have any question on this code part.