VB Web Browser: Wait Until Element is Present - vb.net

Question

Hey!
Simple question, is there any way I can get a webbrowser to wait until an element is present? I'm not an amazing coder, so here's my best example of what I'm trying to do -
Do While PageLoaded = False
Dim OObject As Object
OObject = WebBrowser1.Document.GetElementById("Element-That-I-Need-Loaded")
If (OObject Is Nothing) Then
Pageloaded = False
Else
PageLoaded = True
End If
Loop
The problem with this is that the element doesn't have an ID, so when I'm trying to do something like click it, I have to do something like this -
For Each altelm As HtmlElement In WebBrowser1.Document.GetElementsByTagName("SPAN")
If altelm.GetAttribute("classname").ToString = "Classname-of-Element-I-Need-Loaded" Then
altelm.Focus()
altelm.InvokeMember("click")
End If
I apologise if this is worded poorly, I'm new to this :)
Thanks!

Answer 1

Use a timer that checks for the element periodically. Start the timer in the DocumentCompleted event, then stop it once the element has been found.
Private WithEvents WaitTimer As New Timer With {.Interval = 250}
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
WebBrowser1.Navigate("http://www.somewebsite.com/")
AddHandler WebBrowser1.DocumentCompleted, AddressOf SomeWebsite_DocumentCompleted
End Sub
Private Sub SomeWebsite_DocumentCompleted(sender As Object, e As WebBrowserDocumentCompletedEventArgs)
WaitTimer.Start()
RemoveHandler WebBrowser1.DocumentCompleted, AddressOf SomeWebsite_DocumentCompleted
End Sub
Private Sub WaitTimer_Tick(sender As Object, e As EventArgs) Handles WaitTimer.Tick
'Look for the element every time the timer ticks.
For Each altelm As HtmlElement In WebBrowser1.Document.GetElementsByTagName("SPAN")
If altelm.GetAttribute("className") = "Classname-of-Element-I-Need-Loaded" Then 'No need to call ToString() since GetAttribute() already returns a string.
altelm.Focus()
altelm.InvokeMember("click")
WaitTimer.Stop() 'Element found, stop the timer.
End If
Next
End Sub