如何修复我的自动更新程序VB.Net

Question

您好，我的项目需要一些帮助。所以程序会崩溃，如果它执行一个需要互联网的代码我想知道如何命令我的应用程序检查是否有互联网然后继续，如果有互联网并提示用户连接到互联网如果没有连接到互联网

Public Sub CheckForUpdates()
       If ProgressBar1.Value = 100 Then
           Dim request As System.Net.HttpWebRequest = System.Net.HttpWebRequest.Create("http://dl.dropbox.com/u/46370133/Noter/Version.txt.txt")
           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
           If newestversion.Contains(currentversion) Then
               Button1.Text = ("You are up todate!")
               label2.text = ("You may now close this dialog")
           Else
               Button1.Text = ("Downloading update!")
               WebBrowser1.Navigate("http://dl.dropbox.com/u/46370133/Noter/Noter.exe")
               label2.text = ("You may now close this dialog")
           End If
       End If
Button
Button1.Enabled = False
       Button1.Text = "Checking for updates..."
       Timer1.Start()
       Label1.Text = ProgressBar1.Value
       CheckForUpdates()
timer
ProgressBar1.Increment(5)
               Label1.Text = ProgressBar1.Value
               If ProgressBar1.Value = 100 Then
                   Timer1.Stop()
                   If ProgressBar1.Value = 100 Then
                       Dim request As System.Net.HttpWebRequest = System.Net.HttpWebRequest.Create("http://dl.dropbox.com/u/46370133/Noter/Version.txt.txt")
                       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
                       If newestversion.Contains(currentversion) Then
                   Button1.Text = ("You are up todate!")
                   label2.text = ("You may now close this dialog")
                       Else
                   Button1.Text = ("Downloading update!")
                   WebBrowser1.Navigate("http://dl.dropbox.com/u/46370133/Noter/Noter.exe")
                   label2.text = ("You may now close this dialog")
                       End If
                   End If
               End If

Answer 1

如果My.Computer.Network.Ping（＆＃34; www.Google.com＆＃34;）那么

      MsgBox("Internet Ok")
    Else
      MsgBox("No Internet")

    End If