尝试：

Public count as integer=0

Private Sub WebBrowser_DocumentCompleted(ByVal sender As System.Object,ByVal e As WebBrowserDocumentCompletedEventArgs) _
Handles WebBrowser1.DocumentCompleted

If count<2 then

For Each Element As HtmlElement In WebBrowser2.Document.GetElementsByTagName("a")
If Element.OuterHtml.Contains("btn btn-large play") Then
Element.InvokeMember("click")
End If

count=count+1
end if

End Sub