Adding Controls to the Toolbox

You can specify which category heading any control should be shown under by using the attributes highlighted in the example below. You can also specify which heading a control's properties should appear under.

using System.ComponentModel;

[DisplayName("Masked Text Box")]
[DesignerCategory("Common Controls")]
[Description("The Masked TextBox.")]
public partial class MaskedTextBox : UserControl
{
  public static readonly DependencyProperty MaskProperty =
  DependencyProperty.Register("Mask", typeof(MaskString), typeof(MaskedTextBox),
    new FrameworkPropertyMetadata(new MaskString("AAA"),
new PropertyChangedCallback(OnMaskPropertyChanged)));

  [EditorBrowsable(EditorBrowsableState.Always), Category("Validation"), Description("The mask which will determine whether 
the data entry is valid")]
  public MaskString Mask
  {
    get { return (MaskString)GetValue(MaskProperty) as MaskString; }
    set { SetValue(MaskProperty, value); }