[Rockofello]

Here I have a simple Process creator and I want to use WMI to defrag the hard drive selected and show a progress bar while it works, here is what I have
DefragForm.vb

Code

Imports System.Management

Public Class Defrag
    Dim myProcess As New Process
    Dim myProcessStartInfo As New ProcessStartInfo("c:\Windows\System32\Defrag.exe", "C: /A /U")
    Public Sub Form2_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

        Dim drives As System.IO.DriveInfo() = System.IO.DriveInfo.GetDrives
        For i As Integer = 0 To drives.Length - 1
            ComboBox1.Items.Add(drives(i).ToString)
        Next
        ComboBox1.SelectedIndex = 0
    End Sub
    Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick
        Dim myStreamReader As System.IO.StreamReader = myProcess.StandardOutput
        Dim myString As String = myStreamReader.ReadLine()
        If myString = Nothing Then
        Else
            Label1.Text = myString
        End If
    End Sub
    Sub AetherButton1_Click(sender As Object, e As EventArgs) Handles AetherButton1.Click
        myProcessStartInfo.UseShellExecute = False
        myProcessStartInfo.RedirectStandardOutput = True
        myProcessStartInfo.WindowStyle = ProcessWindowStyle.Hidden
        myProcess.StartInfo = myProcessStartInfo
        myProcess.Start()
        Timer1.Start()
    End Sub


End Class

Was wondering if anyone can shine some light on this.
There errors show on MyProcess.Start() "Failed to find directory"

[stratex]

I'm on mobile so excuse me if some of this is wrong, but I'll try my best.

As long as defrag.exe is running, the commandline aruments that should be passed are:

Code

defrag volume [-a] [-f][-v] [-?]
Parameters

volume
The drive letter or a mount point of the volume to be defragmented

-a
Analyze only

-f
Forces defragmentation of the volume regardless of whether it needs to be defragmented or even if free space is low

-v
Verbose output

-?
Display the help text

So I believe that the ProcessStartInfo should read:

Code

Dim myProcessStartInfo As New ProcessStartInfo("c:\Windows\System32\Defrag.exe", "C")

I'm not sure what your /U argument does but -a is to only analyse the drive which isn't what you said you were wanting.

Although I think this could all be done by using:

Code

Process.Start(<path to defrag>, "C")

I honestly have no idea if this works as I can't test it, so if this wasnt what you were looking for, a quick google search came up with a detailed walkthrough on how to do this with the built in Windows Defragger and WMI

mobile.codeguru.com/columns/vb/defragging-disks-with-vb.net.htm

[Rockofello]

Here what I got from that little snippet

Code

    Private Sub btnDefragWMI_Click( sender As Object,  e As EventArgs) Handles btnDefragWMI.Click
        Try

        
        Dim objWMI As Object 'Create WMI Object

        Dim objDisk As Object 'Disk Object

        Dim colDisks As Object 'Disks Collection

        Dim objResult As Object 'Able To Defragment / Not

        'Get All Disk On System
        objWMI = GetObject("winmgmts:\\" & Environment.MachineName & "\root\cimv2")

            colDisks = objWMI.ExecQuery("Select * from Win32_Volume Where Name = 'Z:\'")

        For Each objDisk In colDisks 'Loop Through All Disks

                objResult = objDisk.Defrag() 'Try To Defrag

            If objResult = 0 Then 'Successful

                    MsgBox("Drive " & objDisk.Name & " Successfully Defragged.")

            Else 'Unsuccessful

                    MsgBox("Unable To Defrag Drive " & objDisk.Name)

            End If

        Next
        Catch ex As Exception
            MsgBox(ex.Message)
        End Try
    End Sub

Although It does nothing at all that I can see, shows no results.