[Kazun]

Код:

Add-Type -AssemblyName System.Windows.Forms
Add-Type -AssemblyName PresentationFramework
[System.Windows.Forms.Application]::EnableVisualStyles()

$Form                           = New-Object system.Windows.Forms.Form
$Form.ClientSize                = '400,400'
$Form.text                      = "Form"
$Form.TopMost                   = $false

$TextBox                        = New-Object system.Windows.Forms.TextBox
$TextBox.multiline              = $false
$TextBox.text                   = "ReadOnly Text"
$TextBox.width                  = 100
$TextBox.height                 = 20
$TextBox.location               = New-Object System.Drawing.Point(150,50)
$TextBox.Font                   = 'Microsoft Sans Serif,10'
$TextBox.ReadOnly               = $true

$ComboBox                       = New-Object system.Windows.Forms.ComboBox
$ComboBox.text                  = "comboBox"
$ComboBox.width                 = 100
$ComboBox.height                = 20
$ComboBox.location              = New-Object System.Drawing.Point(150,81)
$ComboBox.Font                  = 'Microsoft Sans Serif,10'
$ComboBox.DropDownStyle         = "DropDownList"
$ComboBox.Items.AddRange(@(
    "One","Two","Three","Four"
))

$Button                          = New-Object System.Windows.Forms.Button
$Button.Location                 = New-Object System.Drawing.Point(150, 120)
$Button.Size                     = New-Object System.Drawing.Size(98, 23)
$Button.Text                     = "Output"
$Button.add_Click({[System.Windows.MessageBox]::Show($ComboBox.SelectedItem.ToString())})

$Form.controls.AddRange(@($ComboBox,$TextBox,$Button))
$Form.ShowDialog()