DesignerActionPropertyItem Class


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Represents a panel item that is associated with a property in a class derived from DesignerActionList. This class cannot be inherited.

Namespace:   System.ComponentModel.Design
Assembly:  System.Design (in System.Design.dll)


public sealed class DesignerActionPropertyItem : DesignerActionItem

System_CAPS_pubmethodDesignerActionPropertyItem(String, String)

Initializes a new instance of the DesignerActionPropertyItem class, with the specified property and display names.

System_CAPS_pubmethodDesignerActionPropertyItem(String, String, String)

Initializes a new instance of the DesignerActionPropertyItem class, with the specified property and category names, and display text.

System_CAPS_pubmethodDesignerActionPropertyItem(String, String, String, String)

Initializes a new instance of the DesignerActionPropertyItem class, with the specified property and category names, and display and description text.


Gets or sets a value indicating whether to allow this item to be placed into a group of items that have the same Category property value.(Inherited from DesignerActionItem.)


Gets the group name for an item.(Inherited from DesignerActionItem.)


Gets the supplemental text for the item.(Inherited from DesignerActionItem.)


Gets the text for this item.(Inherited from DesignerActionItem.)


Gets the name of the property that this item is associated with.


Gets a reference to a collection that can be used to store programmer-defined key/value pairs.(Inherited from DesignerActionItem.)


Gets or sets a component that contributes its items to the current panel.


Gets or sets a value that indicates whether this item appears in source code view.(Inherited from DesignerActionItem.)


Determines whether the specified object is equal to the current object.(Inherited from Object.)


Serves as the default hash function. (Inherited from Object.)


Gets the Type of the current instance.(Inherited from Object.)


Returns a string that represents the current object.(Inherited from Object.)

The DesignerActionPropertyItem class represents individual items in a smart tag panel. Each item is typically associated with a property in a class that is derived from the DesignerActionList class and supplied by the component author. The association is maintained through the name of the property, as stored in the MemberName property.

Individual panel items are associated together to form a panel by a call to the GetSortedActionItems method of the DesignerActionList class.

To display the value of the associated property, that property must have a get accessor method; to allow editing, the property must have a set accessor method. The way in which the panel allows direct editing of a property item by the user depends on the supporting type information present for the data type of the associated property. The following table shows the likely scheme.

Property type information

Property item editing user interface (UI)

Has an associated type editor (UITypeEditor)

The type editor associated with the underlying property is displayed for editing the property's value.

Has an associated type converter to a known type (TypeConverter)

The type editor for the known type is displayed for editing the property's value. For example, a type converter to String will likely display a TextBox.

Boolean value

The item is displayed using a binary UI, such as a check mark.

None of the above.

The item is displayed as a non-editable text string using the data type's ToString method.

All fundamental types, such as System.Boolean, and common .NET Framework data types, such as System.String, supply standard type converters and editors. For more information about type converters, see How to: Implement a Type Converter or Generalized Type Conversion. For more information about type editors, see How to: Implement a UI Type Editor.

The following code example demonstrates how to create a collection of DesignerActionItem objects. For a full example of implementing smart tags, see How to: Attach Smart Tags to a Windows Forms Component.

public override DesignerActionItemCollection GetSortedActionItems()
    DesignerActionItemCollection items = new DesignerActionItemCollection();

    //Define static section header entries.
    items.Add(new DesignerActionHeaderItem("Appearance"));
    items.Add(new DesignerActionHeaderItem("Information"));

    //Boolean property for locking color selections.
    items.Add(new DesignerActionPropertyItem("LockColors",
                     "Lock Colors", "Appearance",
                     "Locks the color properties."));
    if (!LockColors)
        items.Add(new DesignerActionPropertyItem("BackColor",
                         "Back Color", "Appearance",
                         "Selects the background color."));
        items.Add(new DesignerActionPropertyItem("ForeColor",
                         "Fore Color", "Appearance",
                         "Selects the foreground color."));

        //This next method item is also added to the context menu 
        // (as a designer verb).
        items.Add(new DesignerActionMethodItem(this,
                         "InvertColors", "Invert Colors",
                         "Inverts the fore and background colors.",
    items.Add(new DesignerActionPropertyItem("Text",
                     "Text String", "Appearance",
                     "Sets the display text."));

    //Create entries for static Information section.
    StringBuilder location = new StringBuilder("Location: ");
    StringBuilder size = new StringBuilder("Size: ");
    items.Add(new DesignerActionTextItem(location.ToString(),
    items.Add(new DesignerActionTextItem(size.ToString(),

    return items;

.NET Framework
Available since 2.0

Any public static ( Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

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