Classic Forms Get-DBComboBox example

dbcombobox.ps1

$sqlserver = "sqlserver2014a"

Function Get-SqlDatabases {
  param(
	[Parameter(Mandatory=$true)]
    [string]$SqlServer,
    [object]$Credential
  )
	$paramconn = New-Object System.Data.SqlClient.SqlConnection
	if ($credential.count -eq 0) {
		$paramconn.ConnectionString = "Data Source=$sqlserver;Integrated Security=True;Connection Timeout=3"
	} else {
		$paramconn.ConnectionString = "Data Source=$sqlserver;User Id=$($Credential.UserName); Password=$($Credential.GetNetworkCredential().Password);Connection Timeout=3"
	}
	try {
		$paramconn.Open()
		$sql = "select name from master.dbo.sysdatabases where dbid > 4 order by name"
		$paramcmd = New-Object System.Data.SqlClient.SqlCommand($sql, $paramconn, $null)	
		$datatable = New-Object System.Data.DataTable
		[void]$datatable.Load($paramcmd.ExecuteReader())		
		$databaselist = $datatable.rows.name
		$null = $paramcmd.Dispose()
		$null = $paramconn.Close()
		$null = $paramconn.Dispose()
		return $databaselist
	} catch { throw "Cannot access $sqlserver" }
}

Function Get-DbComboBox {
# Thanks to: http://bit.ly/1Mw9PMn
  param(
    [string]$prompt_message = 'Select database',
    [string[]]$items = @(),
    [string]$caption = "Select Database"
  )

Function PopulateCombo ()
{
  param([string[]]$comboBoxItems)
  for ($i = 0; $i -lt $comboBoxItems.Length; $i++)
  {
    $str = $comboBoxItems[$i]
    if ($str -ne $null)
    {
      [void]$combobox.Items.Add($str)
    }
  }
}
	[System.Reflection.Assembly]::LoadWithPartialName("System.Windows.Forms") | Out-Null
	$script:result = @{ 'text' = ''; 'status' = $null; }
	$script:result.status = [System.Windows.Forms.DialogResult]::None;
	$form = New-Object System.Windows.Forms.Form
	$label_prompt = New-Object System.Windows.Forms.Label
	$button_ok = New-Object System.Windows.Forms.Button
	$button_cancel = New-Object System.Windows.Forms.Button
	$combobox = New-Object System.Windows.Forms.ComboBox
	$form.SuspendLayout()
	$label_prompt.Anchor = [System.Windows.Forms.AnchorStyles]::Top -bor [System.Windows.Forms.AnchorStyles]::Bottom -bor [System.Windows.Forms.AnchorStyles]::Left -bor [System.Windows.Forms.AnchorStyles]::Right
	$label_prompt.BackColor = [System.Drawing.SystemColors]::Control
	$label_prompt.Font = New-Object System.Drawing.Font ('Microsoft Sans Serif',8.25,[System.Drawing.FontStyle]::Regular,[System.Drawing.GraphicsUnit]::Point,0)
	$label_prompt.Location = New-Object System.Drawing.Point (12,9)
	$label_prompt.Name = 'lblPrompt'
	$label_prompt.Size = New-Object System.Drawing.Size (302,82)
	$label_prompt.TabIndex = 3
	$label_prompt.Font = New-Object System.Drawing.Font ('Arial',10,[System.Drawing.FontStyle]::Bold,[System.Drawing.GraphicsUnit]::Point,0)
	$button_ok.DialogResult = [System.Windows.Forms.DialogResult]::OK
	$button_ok.FlatStyle = [System.Windows.Forms.FlatStyle]::Standard
	$button_ok.Location = New-Object System.Drawing.Point (326,8)
	$button_ok.Name = 'btnOK'
	$button_ok.Size = New-Object System.Drawing.Size (64,24)
	$button_ok.TabIndex = 1
	$button_ok.Text = '&OK'
	$button_ok.Add_Click({
	  param([object]$sender,[System.EventArgs]$e)
	  $script:result.status = [System.Windows.Forms.DialogResult]::OK
	  $script:result.Text = $combobox.Text
	  $form.Dispose()
	})
	$button_ok.Font = New-Object System.Drawing.Font ('Arial',10,[System.Drawing.FontStyle]::Bold,[System.Drawing.GraphicsUnit]::Point,0)
	$button_cancel.DialogResult = [System.Windows.Forms.DialogResult]::Cancel
	$button_cancel.FlatStyle = [System.Windows.Forms.FlatStyle]::Standard
	$button_cancel.Location = New-Object System.Drawing.Point (326,40)
	$button_cancel.Name = 'btnCancel'
	$button_cancel.Size = New-Object System.Drawing.Size (64,24)
	$button_cancel.TabIndex = 2
	$button_cancel.Text = '&Cancel'
	$button_cancel.Add_Click({
	  param([object]$sender,[System.EventArgs]$e)
	  $script:result.status = [System.Windows.Forms.DialogResult]::Cancel
	  $script:result.Text = ''
	  $form.Dispose()
	})
	$button_cancel.Font = New-Object System.Drawing.Font ('Arial',10,[System.Drawing.FontStyle]::Bold,[System.Drawing.GraphicsUnit]::Point,0)
	$combobox.Location = New-Object System.Drawing.Point (8,100)
	$combobox.Name = 'CmBxComboBox'
	$combobox.Size = New-Object System.Drawing.Size (379,20)
	$combobox.TabIndex = 0
	$combobox.Text = ''
	$combobox.Font = New-Object System.Drawing.Font ('Arial',10,[System.Drawing.FontStyle]::Regular,[System.Drawing.GraphicsUnit]::Point,0)
	$combobox.Add_TextChanged({param([object]$sender,[System.EventArgs]$e)})
	$combobox.Add_KeyPress({param([object]$sender,[System.Windows.Forms.KeyPressEventArgs]$e)})
	$combobox.Add_TextChanged({param([object]$sender,[System.EventArgs]$e)})
	$form.AutoScaleBaseSize = New-Object System.Drawing.Size (5,13)
	$form.ClientSize = New-Object System.Drawing.Size (398,128)
	$form.Controls.AddRange(@($combobox,$button_cancel,$button_ok,$label_prompt))
	$form.FormBorderStyle = [System.Windows.Forms.FormBorderStyle]::FixedDialog
	$form.MaximizeBox = $false
	$form.MinimizeBox = $false
	$form.Name = 'ComboBoxDialog'
	$form.ResumeLayout($false)
	$form.AcceptButton = $button_ok
	$script:result.status = [System.Windows.Forms.DialogResult]::Ignore
	$script:result.status = ''
	PopulateCombo -comboBoxItems $items
	$label_prompt.Text = $prompt_message
	$form.Text = $caption
	$form.StartPosition = [System.Windows.Forms.FormStartPosition]::CenterScreen
	$combobox.SelectionStart = 0
	$combobox.SelectionLength = $combobox.Text.Length
	[void]$combobox.Focus()
	$form.Name = 'Form1'
	$form.ResumeLayout($false)
	$form.Topmost = $True
	$form.Add_Shown({ $form.Activate() })
	[void]$form.ShowDialog($caller)
	$form.Dispose()
	$form = $null
	return ($script:result).Text

}
$databases = Get-SqlDatabases -SqlServer $sqlserver -Credential $credential
$database = Get-DbComboBox -Items $databases