Question

I am a beginner to C#. I am trying to make a simple program that displays the links from a website into a ListBox. Since retrieving the links takes time, my GUI waits till all the links are parsed and ListBox populated before it becomes visible.

I would assume that this is because the InitializeComponent() and my ParseLinks() methods run in the same thread. I would like to know if there is way I could run ParseLinks() after the UI elements are loaded.

    public mainForm()
    {
        InitializeComponent();
        ParseLinks();
    }

I would appreciate any input. Thanks

[Edit]

More info on ParseLinks(): (I am giving the summary since the code is quite extensive)

ParseLinks() gets the links into an arraylist and assigns the arraylist to the ListBox. The whole operation works very well. But I wanted the GUI to be displayed and then the ListBox populated. I am also disabling a Button while at it and also changing a ProgressBar Style to Marquee. Referring to the response I gave below, when I used Backgroundworker, I got multiple cross-thread operation error which I solved by placing the GUI editing code inside one InvokeRequired statement

Answer 1

If you are using WinForms, I suggest using BackgroundWorker. Your form would populate ListBox in a background thread.
More details here and here.

[Edit]

Here is the basic idea:

public Form1()
{
    InitializeComponent();
    backgroundWorker1.RunWorkerAsync();
}

private void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)
{
    for(var i = 0; i < 1000; i++)
    {
        var newElement = BuildMyElement(i);
        backgroundWorker1.ReportProgress(0, newElement);
    }
}

private void backgroundWorker1_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
    var newElement = (MyType)e.UserState;
    listBox1.Items.Add(newElement);
}

Replace backgroundWorker1_DoWork with the code that you use to retrieve URLs.