[Source] Youtube Download [VB.net]

Code:
Public Class Form1

    Dim HttpRequest As Net.HttpWebRequest

    Dim HttpResponse As Net.HttpWebResponse

    Dim Stream As IO.StreamReader

    Dim scode As String = ""

    Delegate Sub _generateLinks()

    Private Sub generateLinks()

  Dim type As String = ""

  Dim page As String = ""

  Dim tstring As String = ""

  Dim link As Integer = 1

  Dim index As Integer = 0

  Dim count As Integer = 0

  Dim num1 As Integer = 0

  Dim num2 As Integer = 0

  lstIndex.Items.Clear()

  lstLinks.Items.Clear()

  Do Until index = -1

    index = scode.IndexOf("http://v", index + 1)

    If index <> -1 Then

    lstIndex.Items.Add(index)

    End If

  Loop

  For i = 0 To lstIndex.Items.Count - 2

    num1 = lstIndex.Items(i)

    num2 = lstIndex.Items(i + 1)

    If num2 - num1 < 380 Then

    tstring = scode.Substring(num1, num2 - num1)

    Dim right As String = Microsoft.VisualBasic.Right(tstring, 8)

    If right.Substring(0, 1) = "%" Then

    tstring = tstring.Substring(0, tstring.Count - 8)

    Else

    tstring = tstring.Substring(0, tstring.Count - 7)

    End If

    If Not lstLinks.Items.Contains(tstring) Then

    If Not Microsoft.VisualBasic.Right(tstring, 3) = "com" Then

    lstLinks.Items.Add(tstring)

    End If

    End If

    count += 1

    End If

  Next

  index = 0

  For i = 0 To lstLinks.Items.Count - 1

    HttpRequest = Net.HttpWebRequest.Create(New Uri(lstLinks.Items.Item(i)))

    HttpResponse = HttpRequest.GetResponse

    type = HttpResponse.ContentType

    page = page & "<br>" & "<a href = """ & lstLinks.Items(i) & """>" & "Link " & link & "  -  Type: " & type

    link += 1

  Next

  wb.DocumentText = page

  btnGenerate.Enabled = True

    End Sub

    Private Sub btnGenerate_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnGenerate.Click

  Dim t As Threading.Thread

  wb.DocumentText = ""

  btnGenerate.Enabled = False

  t = New Threading.Thread(AddressOf getpage)

  t.Start()

    End Sub

    Private Sub getpage()

  HttpRequest = Net.HttpWebRequest.Create(txtUrl.Text)

  HttpResponse = HttpRequest.GetResponse

  Stream = New IO.StreamReader(HttpResponse.GetResponseStream)

  scode = Stream.ReadToEnd

  'credit to TraptCode for replace codes

  scode = scode.Replace("%3A", ":")

  scode = scode.Replace("%2F", "/")

  scode = scode.Replace("%3F", "?")

  scode = scode.Replace("%3D", "=")

  scode = scode.Replace("%26", "&")

  scode = scode.Replace("%25", "%")

  Invoke(New _generateLinks(AddressOf generateLinks))

    End Sub

End Class