Question Help With LOOP time

[just369]

hi, hope you can help me out

So i got this code, that checks my IPS and returns a message if its online but it was taking long and it wouldnt show the Items found line by line, rather it showed everything at the end of the loop, it loops around 1516 items.


They told me to use a doevents so it can show line by line as the loop its runnin, but doevents makes my CP sloww and when i stop the program in the middle of the process it returns an error that says ARGUMENT OUT OF RANGE EXCEPTION WAS UNHANDLED:Index was out of range. Must be non-negative and less than the size of the collection. Parameter name: index..

I think its the doevents thats doing this....

I want to know if theres anyotehr solution rather the the doevents..

heres my code

Dim hello As String
        Dim sum As Integer

   
        DataGridView2.Rows.Clear()

        If DataGridView1.Visible = False Then
            DataGridView1.Visible = True
            Button2.Visible = True
            Me.Button1.Enabled = True
            DataGridView2.Visible = False
            Botonip.Visible = False
        End If

        Me.Button1.Enabled = False ''i have to disable the button once the program starts because doevents will continue to leave it on while program runs.

        Try
            For sum = 0 To DataGridView1.Rows.Count - 1

                hello = DataGridView1.Rows.Item(sum).Cells.Item(1).Value  ''this checks the ip of rows

                If My.Computer.Network.Ping(hello, 500) Then ''this will ping the ip address and return true or false
                    DataGridView1.Rows.Item(sum).Cells.Item(2).Value = "True" '' this checks or not the checkbox for true or false

                    Try
                        DataGridView1.Rows.Item(sum).Cells.Item(3).Value = System.Net.Dns.GetHostEntry(hello).HostName ''this gets the host name of a computer
                    Catch ex As Exception
                        DataGridView1.Rows.Item(sum).Cells.Item(3).Value = "Error en Host"
                    End Try

                    If DataGridView1.Rows.Item(sum).Cells.Item(3).Value = hello Then
                        Dim Myhostname As String = GetCpname(hello)
                        Dim hostnewname As String() = Myhostname.Split(" "c, "<"c)
                        DataGridView1.Rows.Item(sum).Cells.Item(3).Value = (hostnewname(0))
                    End If


                    Dim Mymac As String = GetMACAddress(hello)
                    Dim MyChar As Char() = {"M"c, "A"c, "C"c, "a"c, "d"c, "d"c, "r"c, "e"c, "e"c, "s"c, " "c, "="c}
                    Dim mynewmac As String = Mymac.TrimStart(MyChar)
                    DataGridView1.Rows.Item(sum).Cells.Item(4).Value = mynewmac

                Else
                    DataGridView1.Rows.Item(sum).Cells.Item(2).Value = "false"
                    DataGridView1.Rows.Item(sum).Cells.Item(3).Value = ""
                    DataGridView1.Rows.Item(sum).Cells.Item(4).Value = ""
                End If
                My.Application.DoEvents()

            Next
            
Finally
            Me.Button1.Enabled = True ''once program end i have to restore the button that enabled the application to check again for IPs online
        End Try



    End Sub

 

[MattP]

Check out the BackgroundWorker control. Here's a nice article showing how to use it: How To Update Controls Using BackgroundWorker in VB.NET