Populate textbox on website vb.net issue

Question

I do a lot of web scraping to automate some of my job functions. I'm trying to populate this text-box on this website .

I've done this on about 10 other websites with no problems, but for some reason, this one is giving me trouble. I've searched all the entries on here from others doing this, but I don't see what I am missing.

Here is my code I am using. I'm using Visual Studio 2008, version 9.0.3. I've also tried invokemember click after setting the attribute etc. It finds the element, so I know I am getting that far, the text-box is just not populating. Any help would be really appreciated.

Thanks.

    theElementCollection = WebBrowser1.Document.GetElementsByTagName("input")
    For Each curElement As HtmlElement In theElementCollection
        If curElement.OuterHtml.Contains("ctl00$CPHContent$txtUserID") Then
            WebBrowser1.Document.GetElementById("ctl00_CPHContent_txtUserID").SetAttribute("value", "TEST")                
            Exit For
        End If
    Next

Answer 1

This is the code I used, and it appears to work fine most of the time.

Private Sub WebBrowser1_DocumentCompleted(sender As Object, e As WebBrowserDocumentCompletedEventArgs) Handles WebBrowser1.DocumentCompleted

    Dim userNameElement As HtmlElement = Nothing

    userNameElement = WebBrowser1.Document.GetElementById("ctl00_CPHContent_txtUserID")
    If Not Nothing Is userNameElement Then
        userNameElement.SetAttribute("value", "TESTing")
    End If

End Sub

Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load

    WebBrowser1.Navigate("https://providerportal.careimprovementplus.com/Login.aspx")

End Sub

The first couple times it wouldn't set the attribute. But after the page was cached it worked perfect every time. There's probably a weird timing issue. I bet if you put a Thread.Sleep(250) as the first statement in the DocumentCompleted event it would solve your problem.