Untitled

[reflection.assembly]::LoadWithPartialName("System.Windows.Forms") | Out-Null
[reflection.assembly]::LoadWithPartialName("System.Drawing") | Out-Null
[System.Windows.Forms.Application]::EnableVisualStyles()

$form = New-Object 'System.Windows.Forms.Form'
$buttonRunProcess = New-Object 'System.Windows.Forms.Button'
$richtextboxOutput = New-Object 'System.Windows.Forms.RichTextBox'
$buttonExit = New-Object 'System.Windows.Forms.Button'

$buttonExit_Click={
    $form.Close()
}

$buttonRunProcess_Click = {
    $buttonRunProcess.Enabled = $false
    $richtextboxOutput.Clear()

    $process = New-Object System.Diagnostics.Process
    $process.StartInfo.FileName = 'ping.exe'
    $process.StartInfo.Arguments = '127.0.0.1'
    $process.StartInfo.UseShellExecute = $false
    $process.StartInfo.CreateNoWindow = $true
    $process.StartInfo.RedirectStandardInput = $false
    $process.StartInfo.RedirectStandardOutput = $true
    $process.EnableRaisingEvents = $true
    $process.SynchronizingObject = $form # this is the important line
    $process.add_OutputDataReceived( {
        # Use $_.Data to access the output text
        $richtextboxOutput.AppendText($_.Data)
        $richtextboxOutput.AppendText("`r`n") }
    )

    $process.Start() | Out-Null
    $process.BeginOutputReadLine()
}

$Form_Closed={
    try
    {
        $buttonRunProcess.remove_Click($buttonRunProcess_Click)
        $buttonExit.remove_Click($buttonExit_Click)
        $form.remove_Form_Closed($processTracker_Form_Closed)
        $form.remove_Form_Closed($Form_Closed)
    }
    catch { Out-Null <# Prevent PSScriptAnalyzer warning #> }
}

$form.SuspendLayout()

$form.Controls.Add($buttonRunProcess)
$form.Controls.Add($richtextboxOutput)
$form.Controls.Add($buttonExit)
$form.ClientSize = [System.Drawing.Size]::new(584, 362)
$form.Margin = '4, 4, 4, 4'
$form.MinimumSize = [System.Drawing.Size]::new(304, 315)
$form.Name = 'Redirect Process Output'
$form.StartPosition = 'CenterScreen'
$form.Text = 'Redirect Process Output'

$buttonRunProcess.Anchor = 'Bottom, Left'
$buttonRunProcess.Location = [System.Drawing.Point]::new(12, 327)
$buttonRunProcess.Name = 'buttonRunProcess'
$buttonRunProcess.Size = [System.Drawing.Size]::new(75, 23)
$buttonRunProcess.TabIndex = 0
$buttonRunProcess.Text = 'Run'
$buttonRunProcess.UseCompatibleTextRendering = $True
$buttonRunProcess.UseVisualStyleBackColor = $True
$buttonRunProcess.add_Click($buttonRunProcess_Click)

$richtextboxOutput.Anchor = 'Top, Bottom, Left, Right'
$richtextboxOutput.HideSelection = $False
$richtextboxOutput.Location = [System.Drawing.Point]::new(12, 12)
$richtextboxOutput.Name = 'richtextboxOutput'
$richtextboxOutput.ReadOnly = $True
$richtextboxOutput.Size = [System.Drawing.Size]::new(559, 305)
$richtextboxOutput.TabIndex = 6
$richtextboxOutput.Text = ''
$richtextboxOutput.WordWrap = $False

$buttonExit.Anchor = 'Bottom, Right'
$buttonExit.Location = [System.Drawing.Point]::new(497, 327)
$buttonExit.Name = 'buttonExit'
$buttonExit.Size =  [System.Drawing.Size]::new(75, 23)
$buttonExit.TabIndex = 2
$buttonExit.Text = 'E&xit'
$buttonExit.UseCompatibleTextRendering = $True
$buttonExit.UseVisualStyleBackColor = $True
$buttonExit.add_Click($buttonExit_Click)

$form.ResumeLayout()

$form.add_Closed($Form_Closed)
$form.ShowDialog()