Method unexpectedly stopping short of completion, c# 2008 .net 3.5

Question

Ok so this is some code im writing to help me out on a game, anyway this stumped me...

ok so this calls my method:

    private void webBrowser1_Navigated(object sender, WebBrowserNavigatedEventArgs e)
    {
        if (webBrowser1.Document.Url.OriginalString.Contains(@"page=logs"))
        {
            AttatchProcess Test = new AttatchProcess();
            Test.LogCleanser(webBrowser1);
        }
    }

And heres the method:

    public void LogCleanser(WebBrowser TargetBrowser)
    {

        if (TargetBrowser.Url.OriginalString.Contains(@"page=logs"))
        {


            Regex FindIP = new Regex(IPExpression);
            HtmlElement LogArea = TargetBrowser.Document.GetElementsByTagName("textarea")[0];
            string log = LogArea.InnerHtml.ToString();

            foreach (Match ipfound in FindIP.Matches(log))
            {
                if (ipfound.Value == MyIP)
                {
                    log.Replace(ipfound.Value, "");
                }
            }

        }

So as soon as the called method hits a line of code assigning an objects value to something in the documents HTML it ends the method, in this case the line:

HtmlElement LogArea = TargetBrowser.Document.GetElementsByTagName("textarea")[0];

is hit and kills the method, any help and ideas much appriciated!

Answer 1

I would guess that there are no <textarea/> elements in the document, therefore causing

TargetBrowser.Document.GetElementsByTagName("textarea")

to be null and your attempt to index the elements array (...ByTagName("textarea")[0]) is causing a NullReferenceException to be throw.

This is all conjecture at this point as your question does not provide enough evidence to know for certain. Are any exceptions being thrown? If so, of what type?

Answer 2

Is log an empty string?

What does FindIP.Matches(log) return?

If log is empty or your regex returns no matches, that would explain why it "drops out".