WPF UI keeps freezing during while loop

Question

During this code my UI freezes and doesn't update like i would like although the console write line works perfectly so im sure it is going through the loop exactly how i want

while (true)
            {
                MyMethod();

            }


            void MyMethod() {
                Console.WriteLine(DateTime.Now);


                TimeSpan duration = SetDate - DateTime.Now;

                int days = duration.Days + 1;
                string strDays = days.ToString();

                string LeftorAgo = "";
                if (strDays[0] == '-')
                {

                    LeftorAgo = "ago";
                }
                else
                {
                    LeftorAgo = "left";
                }

                this.Dispatcher.Invoke(() =>
                {
                    ShowDate.Text = $"{strDays.TrimStart('-')}\n days {LeftorAgo}";
                    ShowSubject.Text = Subject;
                });
                System.Threading.Thread.Sleep(5000);

            }

Edit with Darkonekt's help i solved this issue using his timer technique and it works perfectly thank you! code below

 private System.Windows.Threading.DispatcherTimer remainTimer = new System.Windows.Threading.DispatcherTimer();

InitializeComponent();

            remainTimer.Tick += new EventHandler(MyMethod);
            remainTimer.Interval = TimeSpan.FromSeconds(5);
            remainTimer.Start();



            void MyMethod(object sender, EventArgs e) {
                ...

thank you for your help

Answer 1

Use a DispatcherTimer instead of while loop:

    private DispatcherTimer remainTimer = new DispatcherTimer();

    public MainWindow()
    {
        InitializeComponent();

        remainTimer.Tick += MyMethod;
        remainTimer.Interval = TimeSpan.FromSeconds(5);
        remainTimer.Start();
    }

    private void MyMethod(object sender, EventArgs e)
    {
        Console.WriteLine(DateTime.Now);

        TimeSpan duration = SetDate - DateTime.Now;

        int days = duration.Days + 1;
        string strDays = days.ToString();

        string LeftorAgo = "";
        if (strDays[0] == '-')
        {

            LeftorAgo = "ago";
        }
        else
        {
            LeftorAgo = "left";
        }

        ShowDate.Text = $"{strDays.TrimStart('-')}\n days {LeftorAgo}";
        ShowSubject.Text = Subject;
    }