getelement by class name for clicking - vb.net

Question

I am creating a windows form in VB.NET with web browser control, but not able to click on the below code.
<input type="Submit" class="btn btnSearch bold include_WidthButton" value="Search">
I can click when it is get element by ID, but not by classname. Please help me so much of googling didn't help me.
This is what I tried:
For Each Element As HtmlElement In WebBrowser1.Document.GetElementsByTagName("btn btnSearch bold include_WidthButton")
If Element.OuterHtml.Contains("btn btnSearch bold include_WidthButton") Then
Element.InvokeMember("click")
End If
Exit For

Answer 1

There is no native function to get a collection of elements by class using the webbrowser document. However you can create your own collection using a function and looping through all elements using the document.all property.
Function ElementsByClass(document As HtmlDocument, classname As String)
Dim coll As New Collection
For Each elem As HtmlElement In document.All
If elem.GetAttribute("className").ToLower.Split(" ").Contains(classname.ToLower) Then
coll.Add(elem)
End If
Next
Return coll
End Function
Use would be like this:
Private Sub UpdatBtn_Click(sender As System.Object, e As System.EventArgs) Handles UpdatBtn.Click
For Each elem As HtmlElement In ElementsByClass(WebBrowser1.Document, "form")
elem.SetAttribute("className", elem.GetAttribute("className") & " form-control")
Next
End Sub
I see you are trying to base your collection off the entire className instead of an individual class so you would need to slightly modify.

Answer 2

This is my solution:
Public Sub clickButton(ByVal web As WebBrowser, ByVal tagname As String, ByVal attr As String, ByVal contains As String, ByVal sleep As Integer)
Try
If (web.Document IsNot Nothing) Then
With web.Document
For Each Elem As HtmlElement In .GetElementsByTagName(tagname)
If (Elem.GetAttribute(attr).Contains(contains)) Then
Elem.InvokeMember("Click")
Thread.Sleep(sleep)
Return
End If
Next
End With
End If
Catch ex As Exception
Show_Error(MODULE_NAME, "clickButton")
End Try
End Sub
use:
clickButton(WebBrowser1, "button", "classname", "btn btnSearch bold include_WidthButton", 2000)