Парсинг и отображение только части html-кода источника

Imports System.Net
Public Class Form1
    WithEvents WC As New WebClient
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        WC.DownloadStringAsync(New Uri("http://google.ru"))
    End Sub
    Private Sub WC_DSA(ByVal sender As Object, ByVal e DownloadStringCompletedEventArgs) Handles WC.DownloadStringCompleted
        TextBox1.Text = e.Result
    End Sub
End Class

Imports System
Imports mshtml
Imports System.Text.RegularExpressions
 
Public Class Form1
    Public connection As New XMLHTTPRequest
    Public rgx_tkn As New Regex("token.\:.(?<t>.\d+).", 4)
    Sub sethdrs()
        connection.setRequestHeader("x-requested-with", "XMLHttpRequest")
        connection.setRequestHeader("Cache-Control", "no-cache")
        connection.setRequestHeader("Content-Type", "application/x-www-form-urlencoded; charset=UTF-8")
        connection.setRequestHeader("Accept", "application/json, text/javascript, */*; q=0.01")
    End Sub
    Private Sub RadButton3_Click(sender As Object, e As EventArgs) Handles RadButton3.Click
        connection.open("POST", "https://example.com/login") : sethdrs()
        connection.send("")
        While connection.readyState <> 4 : My.Application.DoEvents() : End While
        If rgx_tkn.IsMatch(connection.responseText) = False Then : MsgBox("error") : Exit Sub : End If
        connection.open("POST", "https://example.com/login") : sethdrs()
        Dim tkn = rgx_tkn.Match(connection.responseText).Groups("t").Value
        connection.send("source=MENU&login=%2BmyLoginsplusom&password=parol&loginToken=" & tkn)
        While connection.readyState <> 4 : My.Application.DoEvents() : End While
    End Sub

Dim tkn = rgx_tkn.Match(connection.responseText).Groups("t").Value