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C# async/await not working with mysql

dragnscalearmor asked:

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I'm trying to get my brain around this async / await thing, and thought I'd try it with a little database app. Below is the code, which works fine, but the GetData() method is not running asynchronously because the UI still freezes when it's connecting/pulling the data. I have the random numbers filling listBox2 as a visual cue that the UI is freezing. The database is just a list of website addresses I made to test this code.

using System;
using System.Windows.Forms;
using MySql.Data.MySqlClient;

namespace MySQLasync
{
    public partial class Form1 : Form
    {
        // public variables and constants
        string strconnect = "Server = localhost; Port=3306; Database=mydbase; Uid=myusername; Pwd=mypasswd;";
        Random r = new Random();
        int c = 0;

        public Form1()
        {
            InitializeComponent();
        }

        private void Button1_Click(object sender, EventArgs e)
        {
            timer1.Enabled = true;
            GetData();
        }

        private async void GetData()
        {
            listBox1.Items.Clear();
            string sql = "SELECT * FROM websites";
            MySqlConnection con1 = new MySqlConnection(strconnect);
            {
                con1.Open();
                MySqlCommand cmd = new MySqlCommand(sql, con1);
                MySqlDataReader reader = (MySqlDataReader)await cmd.ExecuteReaderAsync();
                while (reader.Read())
                {
                    listBox1.Items.Add(reader["title"].ToString());
                }
                con1.Close();
            }
        }

        private void Timer1_Tick(object sender, EventArgs e)
        {
            c++;
            if (c > 20)
            {
                c = 0;
                listBox2.Items.Clear();
            }
            int num = r.Next(1, 999999);
            listBox2.Items.Add(num);
        }
    }
}


What I have tried:

Whether I use async / await or not, the code runs exactly the same. That is, the UI still freezes for the same amount of time as the data is accessed and added to listBox1.

Can someone please explain what I'm doing wrong here? I want the UI to remain responsive while the data is accessed and loaded. Not sure I have the whole concept of async/await yet. Thank you.
Tags: C#

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