Can not add rows to WPF DataGrid in PowerShell

Question

I am using DataGrid from "WPF Toolkit" from PowerShell. The problem is that I can't add new rows using GUI.

dialog.xaml

<Window
  xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
  xmlns:sys="clr-namespace:System;assembly=mscorlib"
  xmlns:dg="clr-namespace:Microsoft.Windows.Controls;assembly=WpfToolkit"
  >

  <Window.Resources>
    <x:Array x:Key="people" Type="sys:Object" />
  </Window.Resources>

  <StackPanel>
    <dg:DataGrid x:Name="_grid" ItemsSource="{DynamicResource people}" CanUserAddRows="True" AutoGenerateColumns="False">
      <dg:DataGrid.Columns>

        <dg:DataGridTextColumn Header="First" Binding="{Binding First}"></dg:DataGridTextColumn>
        <dg:DataGridTextColumn Header="Last" Binding="{Binding Last}"></dg:DataGridTextColumn>

      </dg:DataGrid.Columns>
    </dg:DataGrid>

    <Button>test</Button>
  </StackPanel>
</Window>

dialog.ps1

# Includes
Add-Type -AssemblyName PresentationFramework 
[System.Reflection.Assembly]::LoadFrom("C:\Program Files\WPF Toolkit\v3.5.40320.1\WPFToolkit.dll")

# Helper methods
function LoadXaml
{
    param($fileName)

    [xml]$xaml = [IO.File]::ReadAllText($fileName)
    $reader = (New-Object System.Xml.XmlNodeReader $xaml) 
    [Windows.Markup.XamlReader]::Load( $reader ) 
}

# Load XAML
$form = LoadXaml('.\dialog.xaml')

#
$john = new-object PsObject
$john | Add-Member -MemberType NoteProperty -Name "First" -Value ("John")
$john | Add-Member -MemberType NoteProperty -Name "Last" -Value ("Smith")

$people = @( $john )
$form.Resources["people"] = $people

#
$form.ShowDialog()

run.bat

powershell -sta -file dialog.ps1

The problem seems to be in $people collection. I have tryed same code in C# and it worked, but the collection was defined this way:

List<Person> people = new List<Person>();
people.Add(new Person { First = "John", Last = "Smith" });
this.Resources["people"] = people;

Also tryed the Clr collection - did not work at all:

$people = New-Object "System.Collections.Generic.List``1[System.Object]"
$people.add($john)

Any ideas?

Answer 1

[System.Collections.ArrayList] $people = New-Object "System.Collections.ArrayList"

If you must pass arguments, you should make them strongly-typed, so that PowerShell doesn't wrap it as a PsObject.

http://poshcode.org/68

Answer 2

The final solution:

# Declare Person class
add-type @"
    public class Person
    {
        public Person() {}

        public string First { get; set; }
        public string Last { get; set; }
    }
"@ -Language CsharpVersion3

# Make strongly-typed collection
[System.Collections.ArrayList] $people = New-Object "System.Collections.ArrayList"

# 
$john = new-object Person
$john.First = "John"
$john.Last = "Smith"

$people.add($john)

$form.Resources["people"] = $people