How to convert WebBrowser into WebClient in Windows Service Application - vb.net

Question

Guys I need to convert this into WebClient in Windows Service Application.
Dim webBrowser1 As New WebBrowser
Dim pageready As Boolean = False
Dim timer As System.Diagnostics.Stopwatch = New Stopwatch
Private aTimer As System.Timers.Timer
Dim request As HttpWebRequest = Nothing
Dim webappID As String = String.Empty
Dim appName As String = String.Empty
Public Sub WaitForPageLoad()
Dim dtWebApp As Data.DataTable = BLL.fnListofWebApp()
Dim webappURL As String = String.Empty
If (dtWebApp.Rows.Count > 0) Then
For Each row As DataRow In dtWebApp.Rows
webappURL = (row.Field(Of String)("application_url"))
webappID = (row.Field(Of Integer)("web_apps_id"))
appName = (row.Field(Of String)("application_name"))
serverName = (row.Field(Of String)("server_name"))
Try
webBrowser1.Navigate("webappURL")
request = CType(System.Net.WebRequest.Create(webappURL), System.Net.HttpWebRequest)
request.CookieContainer = New System.Net.CookieContainer
request.Credentials = CredentialCache.DefaultCredentials
CType(request, HttpWebRequest).UserAgent = ".NET Framework Example Client"
timer.Start()
AddHandler webBrowser1.DocumentCompleted, New WebBrowserDocumentCompletedEventHandler(AddressOf PageWaiter)
While Not pageready
Application.DoEvents()
If Not SumState = "" Then
pageready = True
SavingError()
SumState = ""
End If
End While
pageready = False
Catch ex As Exception
SumState = ex.Message
End Try
Next
Else
End If
End Sub
Public Sub SavingError()
timer.Stop()
'Dim timeTaken As TimeSpan = timer.Elapsed
'Dim totalSeconds As String = timeTaken.TotalSeconds()
'Dim RoundedOff As String = (FormatNumber(CDbl(totalSeconds), 2))
'Saving to tblServer_Status
Dim server As New ServerList
Try
Dim RightNow As Date = Now
server.SiteCode = strSiteCode
server.WebAppID = webappID
server.SummaryState = "Critical"
server.LastCheck = DateTime.Now.ToString()
server.NextCheck = RightNow.AddMinutes(30)
server.Duration = 0
BLL.fnInsertWebStat(server)
Catch ex As Exception
SumState = ex.Message
End Try
timer.Reset()
RemoveHandler webBrowser1.DocumentCompleted, New WebBrowserDocumentCompletedEventHandler(AddressOf PageWaiter)
End Sub
Public Sub PageWaiter(ByVal sender As Object, ByVal e As WebBrowserDocumentCompletedEventArgs)
Try
If webBrowser1.ReadyState = WebBrowserReadyState.Complete Then
Dim response As WebResponse = request.GetResponse()
pageready = True
response.Close()
timer.Stop()
Dim server As New ServerList
Try
Dim RightNow As Date = Now
server.SiteCode = strSiteCode
server.WebAppID = webappID
server.SummaryState = "OK"
server.LastCheck = DateTime.Now.ToString()
server.NextCheck = RightNow.AddMinutes(30)
server.Duration = RoundedOff
BLL.fnInsertWebStat(server)
Catch ex As Exception
SumState = ex.Message
End Try
timer.Reset()
RemoveHandler webBrowser1.DocumentCompleted, New WebBrowserDocumentCompletedEventHandler(AddressOf PageWaiter)
End If
Catch ex As Exception
SumState = ex.Message
End Try
End Sub
Help me to configure this into WebClient. Because WebBroser doesn't work in Windows Service Application.
Help?
I badly needed this codes. please help me.