Windows phone C＃将文本更新到GUI mainpage.xaml.cs？

Question

I'm trying to update text from thread to main GUI thread, but exception thrown because it's in different thread. I try to use Dispatcher.CheckAccess(), BeginInvoke() but this project is not Silverlight or WPF. I try the old style InvokeRequired, Invoke(), but these are not available.

StartTest.cs:

    public StartTest(MainPage mainPage)
    {
        mainPageObj = mainPage;
    }

    public async Task RunTest(string testCase)
    {
        await Task.Run(() => RunTestCase(testCase));
    }

    public bool RunTestCase(string testcase)
    {
        switch (testcase)
        {
            case "testcase1":
                int i = 0;
                while (i < 10000)
                {
                    i++;
                }
                mainPageObj.UpdatePassFail(true);//update the main GUI
                break;

            case "testcase2":
                mainPageObj.UpdatePassFail(false);//update the main GUI
                break;
        }

        return false;
    }

Mainpage.xaml.cs:

 public void UpdatePassFail(bool pass)
    {
        try
        {             
            if (pass == true)
            {
                passCount++;
                passFailCount = passCount + failCount;

                textBlock_passTotal.Text = passCount.ToString();
                textBlock_passFailTotal.Text = passFailCount.ToString();
            }
            else if (pass == false)
            {
                failCount++;
                passFailCount = passCount + failCount;

                textBlock_failTotal.Text = failCount.ToString();
                textBlock_passFailTotal.Text = passFailCount.ToString();
            }
        }
        catch(Exception error)
        {
            textBlock_tapInfo.Text = error.Message;
        }            
    }

Update:

After putting the below statements inside the first if-statement, the updated data is shown in main GUI.

Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, () =>
                {
                    textBlock_passTotal.Text = passCount.ToString();
                    textBlock_passFailTotal.Text = passFailCount.ToString();
                });

Answer 1

You should use CoreDispatcher in WP 8.1

CoreDispatcher dispatcher = CoreWindow.GetForCurrentThread().Dispatcher;
await dispatcher.RunAsync(CoreDispatcherPriority.Normal, () => 
{ 
       //UI code goes here
}
);

Refer MSDN link about CoreDispatcher