VB.Net Background Workers in my code? - vb.net

Question

I am a bit of a noobie with vb.net and I made this application that does a lot of http requests and stream reading. But when it does this it always freezes my application.
So I did a little research and found that I could use background workers to solve this. But I have no idea where to start. So if you could look at my code and tell me where and how I can add background workers to prevent the freezing that would be awesome.
Imports mshtml
Imports System.Net
Imports System.Threading
Imports System.Text
Imports System.IO
Imports System.Web
Public Class Form1
Inherits Form
Private Delegate Sub MyDelegate(show As Boolean)
Private demoThread As System.Threading.Thread = Nothing
Private demoThread2 As System.Threading.Thread = Nothing
Private Sub ShowProgressOnThread()
Dim newProgressWindow As New Form2
newProgressWindow.Show()
End Sub
Public Function GetTableText(ByVal sHTML As String) As String
Dim myDoc As mshtml.IHTMLDocument2 = New mshtml.HTMLDocument
Dim mElement As mshtml.IHTMLElement
Dim mElement2 As mshtml.IHTMLElement
Dim mECol As mshtml.IHTMLElementCollection
'initialize the document object within the HTMLDocument class...
myDoc.close()
myDoc.open("about:blank")
'write the HTML to the document using the MSHTML "write" method...
Dim clsHTML() As Object = {sHTML}
myDoc.write(clsHTML)
clsHTML = Nothing
mElement = myDoc.body()
mECol = mElement.getElementsByTagName("TD")
Dim gData As ListViewItem
For A = 3 To mECol.length - 1 Step +6
mElement2 = mECol.item(A)
gData = Me.ListView1.Items.Add(mElement2.innerText)
mElement2 = mECol.item(A - 1)
gData.SubItems.Add(mElement2.innerText.ToUpper)
'Frm.Close()
' lstResults.Items.Add("Game : " & mElement2.innerText)
Next
End Function
Private Sub wait(ByVal interval As Integer)
Dim sw As New Stopwatch
sw.Start()
Do While sw.ElapsedMilliseconds < interval
' Allows UI to remain responsive
Application.DoEvents()
Loop
sw.Stop()
End Sub
Private Sub Button__()
Me.ResetText()
Me.ToolStripStatusLabel1.Text = "Loading..."
Me.Text = "Game Finder | By Unh0ly | Loading..."
' Me.demoThread = New Thread( _
'New ThreadStart(AddressOf Me.Loader))
' Me.demoThread.Start()
'Me.Invoke(New MethodInvoker(AddressOf Me.Loader))
'Me.Frm.Show()
'Application.Run(Frm)
Dim srchText As String
srchText = TextBox1.Text.Replace(" ", "%20")
Dim request As HttpWebRequest = HttpWebRequest.Create("****" & srchText)
'Dim response As HttpWebResponse
Dim response As HttpWebResponse = request.GetResponse()
Dim sr As System.IO.StreamReader = New System.IO.StreamReader(response.GetResponseStream())
Dim sourcecode As String = sr.ReadToEnd()
If sourcecode.Contains("<td>") Then
GetTableText(sourcecode)
Me.ResetText()
Me.Text = "Game Finder | By Unh0ly"
Me.ToolStripStatusLabel1.Text = "Done"
Call wait(2500)
Me.ToolStripStatusLabel1.Text = "Status.."
'newProgressWindow.Hide()
'newProgressWindow.Dispose()
'Form2.Refresh()
ElseIf Not sourcecode.Contains("<td>") Then
' newProgressWindow.Hide()
' Progress.Dispose()
MessageBox.Show("No Results Found For: " + TextBox1.Text)
End If
'Dim sHTML = sourcecode
'For I = 2 To mECol.length - 1 Step +6
End Sub
Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click
'Frm.Show()
Me.Invoke(New MethodInvoker(AddressOf Button__))
'Dim demoThread As System.Threading.Thread
End Sub
Private Sub CopyToolStripMenuItem_Click(sender As System.Object, e As System.EventArgs) Handles CopyToolStripMenuItem.Click, IDAndGameNameToolStripMenuItem.Click
Try
Dim s As String
Dim lsvrow
lsvrow = ListView1.SelectedItems(0)
s = "Game Name: " + lsvrow.Text + ControlChars.NewLine + "ID: " + TextBox2.Text
Clipboard.SetDataObject(s)
Catch ex As System.Exception
MessageBox.Show("Error: " + ex.Message)
Finally
' Perform any tidy up code.
End Try
End Sub
Private Sub CopyIDToolStripMenuItem_Click(sender As System.Object, e As System.EventArgs) Handles CopyIDToolStripMenuItem.Click, IDToolStripMenuItem.Click
Try
Dim s As String
Dim lsvrow
lsvrow = ListView1.SelectedItems(0)
s = TextBox2.Text
Clipboard.SetDataObject(s)
Catch ex As System.Exception
MessageBox.Show("Error: " + ex.Message)
Finally
' Perform any tidy up code.
End Try
End Sub
Private Sub ListView1_ItemActivate(sender As System.Object, e As System.Windows.Forms.ListViewItemSelectionChangedEventArgs) Handles ListView1.ItemSelectionChanged
TextBox2.Text = e.Item.SubItems(1).Text
End Sub
Private Sub TextBox1_KeyDown(sender As System.Object, e As System.Windows.Forms.KeyEventArgs) Handles TextBox1.KeyDown
If e.KeyCode = Keys.Enter Then
'Runs the Button1_Click Event
Button1_Click(Me, EventArgs.Empty)
End If
End Sub
Private Sub Form1_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
End Sub
Private Sub Button2_Click(sender As System.Object, e As System.EventArgs) Handles Button2.Click, ClearToolStripMenuItem.Click
ListView1.Items.Clear()
End Sub
Private Sub DownloadGPDToolStripMenuItem_Click(sender As System.Object, e As System.EventArgs) Handles DownloadGPDToolStripMenuItem.Click, DownloadGPDToolStripMenuItem1.Click
Dim gpds As ArrayList = New ArrayList()
Const YOUR_DIRECTORY As String = "****"
' Get the object used to communicate with the server.
Dim request As FtpWebRequest = CType(WebRequest.Create(YOUR_DIRECTORY), FtpWebRequest)
request.Method = WebRequestMethods.Ftp.ListDirectoryDetails
' This example assumes the FTP site uses anonymous logon.
request.Credentials = New NetworkCredential("****", "****")
Call wait(1500)
Dim response As FtpWebResponse = CType(request.GetResponse, FtpWebResponse)
Dim responseStream As Stream = response.GetResponseStream
Dim reader As StreamReader = New StreamReader(responseStream)
Dim s = reader.ReadToEnd
reader.Close()
response.Close()
If Len(TextBox2.Text) > 0 Then
If s.Contains(TextBox2.Text + ".gpd") Then
FolderBrowserDialog1.ShowDialog()
If Not FolderBrowserDialog1.SelectedPath = Nothing Then
Me.Text = "Game Finder | By Unh0ly | Downloading..."
Me.ToolStripStatusLabel1.Text = "Downloading..."
My.Computer.Network.DownloadFile("****" + TextBox2.Text + ".gpd", FolderBrowserDialog1.SelectedPath + "\" + TextBox2.Text + ".gpd", "", "", False, "100", True)
Me.ResetText()
Me.ToolStripStatusLabel1.Text = "Status.."
ElseIf FolderBrowserDialog1.SelectedPath = Nothing Then
Else
MessageBox.Show("No GPD for Selected Game")
End If
Else
MessageBox.Show("No GPD for Selected Game")
End If
Else
' Do Nothing
End If
End Sub
Private Sub ExitToolStripMenuItem_Click(sender As System.Object, e As System.EventArgs) Handles ExitToolStripMenuItem.Click
Application.Exit()
End Sub
Private Sub CheckForUpdatesToolStripMenuItem_Click(sender As System.Object, e As System.EventArgs) Handles CheckForUpdatesToolStripMenuItem.Click
Dim request As System.Net.HttpWebRequest = System.Net.HttpWebRequest.Create("****")
Dim response As System.Net.HttpWebResponse = request.GetResponse()
Dim sr As System.IO.StreamReader = New System.IO.StreamReader(response.GetResponseStream())
Dim newestversion As String = sr.ReadToEnd()
Dim currentversion As String = Application.ProductVersion
Dim request1 As System.Net.HttpWebRequest = System.Net.HttpWebRequest.Create("****")
Dim response1 As System.Net.HttpWebResponse = request1.GetResponse()
Dim sr1 As System.IO.StreamReader = New System.IO.StreamReader(response1.GetResponseStream())
Dim updurl As String = sr1.ReadToEnd()
If newestversion.Contains(currentversion) Then
MessageBox.Show("You have the current version", "Up to date", MessageBoxButtons.OK, MessageBoxIcon.Information)
Else
Dim result1 As DialogResult = MessageBox.Show("Newer version available" & vbCrLf & "Please Goto *** to check" + vbCrLf + "Do you want to go there now?", "Update Available", MessageBoxButtons.YesNo, MessageBoxIcon.Information)
If result1 = DialogResult.Yes Then
Process.Start(updurl)
Else
' Do Nothing
End If
End If
End Sub
Private Sub AboutToolStripMenuItem_Click(sender As System.Object, e As System.EventArgs) Handles AboutToolStripMenuItem.Click
Dim gpds As ArrayList = New ArrayList()
Const YOUR_DIRECTORY As String = "****"
Dim request As FtpWebRequest = CType(WebRequest.Create(YOUR_DIRECTORY), FtpWebRequest)
request.Method = WebRequestMethods.Ftp.ListDirectoryDetails
request.Credentials = New NetworkCredential("****", "****")
Call wait(100)
Dim response As FtpWebResponse = CType(request.GetResponse, FtpWebResponse)
Dim responseStream As Stream = response.GetResponseStream
Dim reader As StreamReader = New StreamReader(responseStream)
Dim s = reader.ReadToEnd
reader.Close()
response.Close()
Dim Lines() As String = s.Split(New String() {Environment.NewLine}, StringSplitOptions.RemoveEmptyEntries)
MessageBox.Show("Made By Unh0ly aka Nickdudego3" & vbCrLf & "Number of GPD's: " & Lines.Length - 5 & vbCrLf & "Version: " & Application.ProductVersion, "About", MessageBoxButtons.OK, MessageBoxIcon.Asterisk)
End Sub
End Class

Answer 1

Here's a small sample how to use a worker..
Friend WithEvents myWorker As System.ComponentModel.BackgroundWorker
Me.myWorker = New System.ComponentModel.BackgroundWorker()
Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click
myWorker.RunWorkerAsync()
End Sub
Private Sub myWorker_DoWork(ByVal sender As System.Object, ByVal e As System.ComponentModel.DoWorkEventArgs) Handles myWorker.DoWork
'do your stuff here...
End Sub

Answer 2

The best way to find bottle neck in your code is to put Timer.Start and Timer.Stop around your methods to find out which methods are taking the longest to excute.
Once you find the offending methods, you can use ThreadPool.QueueUserWorkItem to implement a basic background threading. Threading is by no means easy and it would take some time for you figure it out all the crazy and weird things that happen when you play with threads.
Hope this helps. If you have any more question, do ask.