ControlDesigner Class
Definition
Important
Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.
Provides a base control designer class for extending the design-mode behavior of a Web server control.
public ref class ControlDesigner : System::Web::UI::Design::HtmlControlDesignerpublic class ControlDesigner : System.Web.UI.Design.HtmlControlDesignertype ControlDesigner = class
inherit HtmlControlDesignerPublic Class ControlDesigner
Inherits HtmlControlDesigner- Inheritance
- Derived
Examples
The following code example demonstrates how to create a simple designer class that derives from the ControlDesigner class. This control designer supports a custom TextControl class and provides a command to change the text size of a control at design time. The control designer is associated with the control by specifying the control designer in a DesignerAttribute object declaration on the TextControl class. The key to persisting property changes from the control designer to the HTML markup is found in the ToggleTextSize method of the custom ActionList class.
To try the example, add a reference to the System.Design.dll assembly and compile the code.
using System;
using System.Web.UI;
using System.Drawing;
using System.Web.UI.Design;
using System.Web.UI.WebControls;
using System.ComponentModel;
using System.ComponentModel.Design;
namespace ASPNet.Design.Samples.CS
{
// Simple text Web control renders a text string.
// This control is associated with the TextSizeWebControlDesigner.
[DesignerAttribute(typeof(TextSizeWebControlDesigner)),
ToolboxData("<{0}:TextControl runat=\"server\"></{0}:TextControl>")]
public class TextControl : Label
{
private bool _largeText = true;
// Constructor
public TextControl()
{
Text = "Test Phrase";
SetSize();
}
// Determines whether the text is large or small
[Bindable(true), Category("Appearance"), DefaultValue("true")]
public bool LargeText
{
get { return _largeText; }
set
{
_largeText = value;
SetSize();
}
}
// Applies the LargeText property to the control
private void SetSize()
{
if (LargeText)
this.Font.Size = FontUnit.XLarge;
else
this.Font.Size = FontUnit.Small;
}
}
// This control designer offers DesignerActionList commands
// that can alter the design time html of the associated control.
public class TextSizeWebControlDesigner : ControlDesigner
{
private DesignerActionListCollection _actionLists = null;
// Do not allow direct resizing of the control
public override bool AllowResize
{
get { return false; }
}
// Return a custom ActionList collection
public override DesignerActionListCollection ActionLists
{
get
{
if (_actionLists == null)
{
_actionLists = new DesignerActionListCollection();
_actionLists.AddRange(base.ActionLists);
// Add a custom DesignerActionList
_actionLists.Add(new ActionList(this));
}
return _actionLists;
}
}
public class ActionList : DesignerActionList
{
private TextSizeWebControlDesigner _parent;
private DesignerActionItemCollection _items;
// Constructor
public ActionList(TextSizeWebControlDesigner parent)
: base(parent.Component)
{
_parent = parent;
}
// Create the ActionItem collection and add one command
public override DesignerActionItemCollection GetSortedActionItems()
{
if (_items == null)
{
_items = new DesignerActionItemCollection();
_items.Add(new DesignerActionMethodItem(this, "ToggleLargeText", "Toggle Text Size", true));
}
return _items;
}
// ActionList command to change the text size
private void ToggleLargeText()
{
// Get a reference to the parent designer's associated control
TextControl ctl = (TextControl)_parent.Component;
// Get a reference to the control's LargeText property
PropertyDescriptor propDesc = TypeDescriptor.GetProperties(ctl)["LargeText"];
// Get the current value of the property
bool v = (bool)propDesc.GetValue(ctl);
// Toggle the property value
propDesc.SetValue(ctl, !v);
}
}
}
}
Imports System.Web.UI
Imports System.Web.UI.Design
Imports System.Web.UI.WebControls
Imports System.ComponentModel
Imports System.ComponentModel.Design
Namespace ASPNet.Design.Samples.VB
' Simple text Web control renders a text string.
' This control is associated with the TextSizeWebControlDesigner.
<DesignerAttribute(GetType(TextSizeWebControlDesigner)), _
ToolboxData("<{0}:TextControl runat='server'></{0}:TextControl>")> _
Public Class TextControl
Inherits Label
Private _largeText As Boolean = True
' Constructor
Public Sub New()
Text = "Test Phrase"
SetSize()
End Sub
' Determines whether the text is large or small
<Bindable(True), Category("Appearance"), DefaultValue(True)> _
Public Property LargeText() As Boolean
Get
Return _largeText
End Get
Set(ByVal value As Boolean)
_largeText = value
SetSize()
End Set
End Property
' Applies the LargeText property to the control
Private Sub SetSize()
If LargeText Then
Me.Font.Size = FontUnit.XLarge
Else
Me.Font.Size = FontUnit.Small
End If
End Sub
End Class
' This control designer offers DesignerActionList commands
' that can alter the design time html of the associated control.
Public Class TextSizeWebControlDesigner
Inherits ControlDesigner
Private _actionLists As DesignerActionListCollection
' Do not allow direct resizing of the control
Public Overrides ReadOnly Property AllowResize() As Boolean
Get
Return False
End Get
End Property
' Return a custom ActionList collection
Public Overrides ReadOnly Property ActionLists() As System.ComponentModel.Design.DesignerActionListCollection
Get
If IsNothing(_actionLists) Then
_actionLists = New DesignerActionListCollection()
_actionLists.AddRange(MyBase.ActionLists)
' Add a custom DesignerActionList
_actionLists.Add(New ActionList(Me))
End If
Return _actionLists
End Get
End Property
' Create a custom class of DesignerActionList
Public Class ActionList
Inherits DesignerActionList
Private _parent As TextSizeWebControlDesigner
Private _items As DesignerActionItemCollection
' Constructor
Public Sub New(ByRef parent As TextSizeWebControlDesigner)
MyBase.New(parent.Component)
_parent = parent
End Sub
' Create the ActionItem collection and add one command
Public Overrides Function GetSortedActionItems() As DesignerActionItemCollection
If IsNothing(_items) Then
_items = New DesignerActionItemCollection()
_items.Add(New DesignerActionMethodItem(Me, "ToggleLargeText", "Toggle Text Size", True))
End If
Return _items
End Function
' ActionList command to change the text size
Private Sub ToggleLargeText()
' Get a reference to the parent designer's associated control
Dim ctl As TextControl = CType(_parent.Component, TextControl)
' Get a reference to the control's LargeText property
Dim propDesc As PropertyDescriptor = TypeDescriptor.GetProperties(ctl)("LargeText")
' Get the current value of the property
Dim v As Boolean = CType(propDesc.GetValue(ctl), Boolean)
' Toggle the property value
propDesc.SetValue(ctl, (Not v))
End Sub
End Class
End Class
End Namespace
<%@ Page Language="C#" %>
<%@ Register TagPrefix="aspSample"
Namespace="ASPNet.Design.Samples.CS" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>Untitled Page</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<aspSample:TextControl ID="TextControl1" runat="server">
</aspSample:TextControl>
</div>
</form>
</body>
</html>
<%@ Page Language="VB" %>
<%@ Register TagPrefix="aspSample"
Namespace="ASPNet.Design.Samples.VB" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>Untitled Page</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<aspSample:TextControl ID="TextControl1" runat="server">
</aspSample:TextControl>
</div>
</form>
</body>
</html>
Remarks
The ControlDesigner class provides a base control designer class that can be inherited from and extended to provide design-time support for a Web server control in a design host, such as Visual Studio 2005.
The object model for working with design-time rendering is improved over earlier versions, with the following new base classes to provide access to the simplified object model:
ControlDesigner, which is not new, but has been greatly improved.
Automatic Formatting
You can create a variety of automatic and pre-defined formats that can simplify the process of page developers who are applying complex style changes to custom Web server controls. For example, the TableDesigner control, which derives from the ControlDesigner class, provides many automatic formats from which to choose. To implement and provide automatic formatting in your custom controls, use the following features:
The AutoFormats property.
The OnAutoFormatApplied method.
The DesignerAutoFormat class.
The DesignerAutoFormatStyle class.
Action Lists (Smart Tags)
Action lists are menus of important or widely used tasks that a page developer who uses a control can perform in a design-time user interface (UI), such as Visual Studio 2005. For example, the design-time view of your control could provide a menu of available tasks. This includes a task to format the control automatically. To learn about action lists, start with the following features:
The ActionLists property.
The DesignerActionList class.
The GetSortedActionItems method.
The DesignerActionListCollection class.
The DesignerActionMethodItem class.
The DesignerActionPropertyItem class.
Control Designer Regions
Regions are editable areas in the design-time view of a Web server control. This feature offers WYSIWYG-like editing of the template content, inner controls, and properties at design time. You can have the control designer create controls in regions or you can use the Toolbox to drag and drop controls into regions. Regions are managed with the following features:
The OnClick method.
The DesignerRegion class.
The EditableDesignerRegion class.
The GetEditableDesignerRegionContent method.
The SetEditableDesignerRegionContent method.
Templates
The model for creating a UI for design-time editing of templated controls, such as the GridView control, has been greatly improved from earlier versions. You can create complex custom controls that include templates for various parts of the control, and your custom control designer can help page developers who are modifying templates with the following features:
The TemplateGroups property.
The InTemplateMode property.
The TemplateGroup class.
Design-Time Rendering
The ControlDesigner class has the following methods to support design-time rendering of the Web server control. Most of these methods are the same as in earlier versions:
The GetDesignTimeHtml method.
The GetEmptyDesignTimeHtml method.
The GetErrorDesignTimeHtml method.
The UpdateDesignTimeHtml method.
The CreatePlaceHolderDesignTimeHtml method.
Constructors
| ControlDesigner() |
Initializes a new instance of the ControlDesigner class. |
Properties
| ActionLists |
Gets the action list collection for the control designer. |
| ActionLists |
Gets the design-time action lists supported by the component associated with the designer. (Inherited from ComponentDesigner) |
| AllowResize |
Gets a value indicating whether the control can be resized in the design-time environment. |
| AssociatedComponents |
Gets the collection of components associated with the component managed by the designer. (Inherited from ComponentDesigner) |
| AutoFormats |
Gets the collection of predefined automatic formatting schemes to display in the Auto Format dialog box for the associated control at design time. |
| Behavior |
Obsolete.
Gets or sets the DHTML behavior that is associated with the designer. (Inherited from HtmlControlDesigner) |
| Component |
Gets the component this designer is designing. (Inherited from ComponentDesigner) |
| DataBindings |
Gets the data bindings collection for the current control. (Inherited from HtmlControlDesigner) |
| DataBindingsEnabled |
Gets a value indicating whether data binding is supported by the containing region for the associated control. |
| DesignerState |
Gets an object that is used to persist data for the associated control at design time. |
| DesignTimeElement |
Obsolete.
Gets the design-time object representing the control that is associated with the HtmlControlDesigner object on the design surface. (Inherited from HtmlControlDesigner) |
| DesignTimeElementView |
Obsolete.
Gets the view-control object for the control designer. |
| DesignTimeHtmlRequiresLoadComplete |
Obsolete.
Gets a value indicating whether the design host must finish loading before the GetDesignTimeHtml method can be called. |
| Expressions |
Gets the expression bindings for the current control at design time. (Inherited from HtmlControlDesigner) |
| HidePropertiesInTemplateMode |
Gets a value indicating whether the properties of the associated control are hidden when the control is in template mode. |
| ID |
Gets or sets the ID string for the control. |
| InheritanceAttribute |
Gets an attribute that indicates the type of inheritance of the associated component. (Inherited from ComponentDesigner) |
| Inherited |
Gets a value indicating whether this component is inherited. (Inherited from ComponentDesigner) |
| InTemplateMode |
Gets a value indicating whether the control is in either template viewing or editing mode in the design host. The InTemplateMode property is read-only. |
| IsDirty |
Obsolete.
Gets or sets a value indicating whether the Web server control has been marked as changed. |
| ParentComponent |
Gets the parent component for this designer. (Inherited from ComponentDesigner) |
| ReadOnly |
Obsolete.
Gets or sets a value indicating whether the properties of the control are read-only at design time. |
| RootDesigner |
Gets the control designer for the Web Forms page that contains the associated control. |
| SetTextualDefaultProperty | (Inherited from ComponentDesigner) |
| ShadowProperties |
Gets a collection of property values that override user settings. (Inherited from ComponentDesigner) |
| ShouldCodeSerialize |
Obsolete.
Gets or sets a value indicating whether to create a field declaration for the control in the code-behind file for the current design document during serialization. (Inherited from HtmlControlDesigner) |
| Tag |
Gets an object representing the HTML markup element for the associated control. |
| TemplateGroups |
Gets a collection of template groups, each containing one or more template definitions. |
| UsePreviewControl |
Gets a value indicating whether the control designer uses a temporary preview control to generate the design-time HTML markup. |
| Verbs |
Gets the design-time verbs supported by the component that is associated with the designer. (Inherited from ComponentDesigner) |
| ViewControl |
Gets or sets a Web server control that can be used for previewing the design-time HTML markup. |
| ViewControlCreated |
Gets or sets a value indicating whether a |
| Visible |
Gets a value that indicates whether the control is visible at design time. |
Methods
| CreateErrorDesignTimeHtml(String) |
Creates HTML markup to display a specified error message at design time. |
| CreateErrorDesignTimeHtml(String, Exception) |
Creates the HTML markup to display a specified exception error message at design time. |
| CreatePlaceHolderDesignTimeHtml() |
Provides a simple rectangular placeholder representation that displays the type and ID of the control. |
| CreatePlaceHolderDesignTimeHtml(String) |
Provides a simple rectangular placeholder representation that displays the type and ID of the control, and also additional specified instructions or information. |
| CreateViewControl() |
Returns a copy of the associated control for viewing or rendering on the design surface. |
| Dispose() |
Releases all resources used by the ComponentDesigner. (Inherited from ComponentDesigner) |
| Dispose(Boolean) |
Releases the unmanaged resources that are used by the HtmlControlDesigner object and optionally releases the managed resources. (Inherited from HtmlControlDesigner) |
| DoDefaultAction() |
Creates a method signature in the source code file for the default event on the component and navigates the user's cursor to that location. (Inherited from ComponentDesigner) |
| Equals(Object) |
Determines whether the specified object is equal to the current object. (Inherited from Object) |
| GetBounds() |
Retrieves the coordinates of the rectangle representing the boundaries for the control as displayed on the design surface. |
| GetDesignTimeHtml() |
Retrieves the HTML markup that is used to represent the control at design time. |
| GetDesignTimeHtml(DesignerRegionCollection) |
Retrieves the HTML markup to display the control and populates the collection with the current control designer regions. |
| GetDesignTimeResourceProviderFactory(IServiceProvider) |
Returns an appropriate resource provider factory, depending on the globalization settings in the configuration file for the site. |
| GetEditableDesignerRegionContent(EditableDesignerRegion) |
Returns the content for an editable region of the design-time view of the associated control. |
| GetEmptyDesignTimeHtml() |
Retrieves the HTML markup to represent a Web server control at design time that will have no visual representation at run time. |
| GetErrorDesignTimeHtml(Exception) |
Retrieves the HTML markup that provides information about the specified exception. |
| GetHashCode() |
Serves as the default hash function. (Inherited from Object) |
| GetPersistenceContent() |
Retrieves the persistable inner HTML markup of the control at design time. |
| GetPersistInnerHtml() |
Obsolete.
Retrieves the persistable inner HTML markup of the control. |
| GetService(Type) |
Attempts to retrieve the specified type of service from the design mode site of the designer's component. (Inherited from ComponentDesigner) |
| GetType() |
Gets the Type of the current instance. (Inherited from Object) |
| GetViewRendering() |
Retrieves an object that contains the design-time markup for the content and regions of the associated control. |
| GetViewRendering(Control) |
Retrieves an object that contains the design-time markup for the content and regions of the specified control. |
| GetViewRendering(ControlDesigner) |
Retrieves an object that contains the design-time markup for the content and regions of the associated control for the specified control designer. |
| Initialize(IComponent) |
Initializes the control designer and loads the specified component. |
| InitializeExistingComponent(IDictionary) |
Reinitializes an existing component. (Inherited from ComponentDesigner) |
| InitializeNewComponent(IDictionary) |
Initializes a newly created component. (Inherited from ComponentDesigner) |
| InitializeNonDefault() |
Obsolete.
Obsolete.
Initializes the settings for an imported component that is already initialized to settings other than the defaults. (Inherited from ComponentDesigner) |
| Invalidate() |
Invalidates the whole area of the control that is displayed on the design surface and signals the control designer to redraw the control. |
| Invalidate(Rectangle) |
Invalidates the specified area of the control that is displayed on the design surface and signals the control designer to redraw the control. |
| InvokeGetInheritanceAttribute(ComponentDesigner) |
Gets the InheritanceAttribute of the specified ComponentDesigner. (Inherited from ComponentDesigner) |
| InvokeTransactedChange(IComponent, TransactedChangeCallback, Object, String) |
Wraps a series of changes into a transaction, using the specified parameters that can be rolled back as a unit with the undo functionality of the design host. |
| InvokeTransactedChange(IComponent, TransactedChangeCallback, Object, String, MemberDescriptor) |
Wraps a series of changes into a transaction, using the specified parameters that can be rolled back as a unit with the undo functionality of the design host. |
| InvokeTransactedChange(IServiceProvider, IComponent, TransactedChangeCallback, Object, String, MemberDescriptor) |
Wraps a series of changes into a transaction, using the specified parameters that can be rolled back as a unit with the undo functionality of the design host. |
| IsPropertyBound(String) |
Obsolete.
Retrieves a value indicating whether the specified property on the associated control is data-bound. |
| Localize(IDesignTimeResourceWriter) |
Uses the provided resource writer to persist the localizable properties of the associated control to a resource in the design host. |
| MemberwiseClone() |
Creates a shallow copy of the current Object. (Inherited from Object) |
| OnAutoFormatApplied(DesignerAutoFormat) |
Called when a predefined, automatic formatting scheme has been applied to the associated control. |
| OnBehaviorAttached() |
Called when the control designer is attached to a Behavior object. |
| OnBehaviorAttached() |
Obsolete.
Called when a behavior is associated with the element. (Inherited from HtmlControlDesigner) |
| OnBehaviorDetaching() |
Obsolete.
Called when a behavior disassociates from the element. (Inherited from HtmlControlDesigner) |
| OnBindingsCollectionChanged(String) |
Obsolete.
Called when the data-binding collection changes. |
| OnClick(DesignerRegionMouseEventArgs) |
Called by the design host when the user clicks the associated control at design time. |
| OnComponentChanged(Object, ComponentChangedEventArgs) |
Called when the associated control changes. |
| OnComponentChanging(Object, ComponentChangingEventArgs) |
Represents the method that will handle the ComponentChanging event for the associated control. |
| OnControlResize() |
Obsolete.
Called when the associated Web server control has been resized in the design host at design time. |
| OnPaint(PaintEventArgs) |
Called when the control designer draws the associated control on the design surface, if the CustomPaint value is |
| OnSetComponentDefaults() |
Obsolete.
Obsolete.
Sets the default properties for the component. (Inherited from ComponentDesigner) |
| OnSetParent() |
Provides a way to perform additional processing when the associated control is attached to a parent control. (Inherited from HtmlControlDesigner) |
| PostFilterAttributes(IDictionary) |
Allows a designer to change or remove items from the set of attributes that it exposes through a TypeDescriptor. (Inherited from ComponentDesigner) |
| PostFilterEvents(IDictionary) |
Allows a designer to change or remove items from the set of events that it exposes through a TypeDescriptor. (Inherited from ComponentDesigner) |
| PostFilterProperties(IDictionary) |
Allows a designer to change or remove items from the set of properties that it exposes through a TypeDescriptor. (Inherited from ComponentDesigner) |
| PreFilterAttributes(IDictionary) |
Allows a designer to add to the set of attributes that it exposes through a TypeDescriptor. (Inherited from ComponentDesigner) |
| PreFilterEvents(IDictionary) |
Sets the list of events that are exposed at design-time for the TypeDescriptor object for the component. (Inherited from HtmlControlDesigner) |
| PreFilterProperties(IDictionary) |
Adds properties to or removes properties from the Properties grid in a design host at design time or provides new design-time properties that might correspond to properties on the associated control. |
| RaiseComponentChanged(MemberDescriptor, Object, Object) |
Notifies the IComponentChangeService that this component has been changed. (Inherited from ComponentDesigner) |
| RaiseComponentChanging(MemberDescriptor) |
Notifies the IComponentChangeService that this component is about to be changed. (Inherited from ComponentDesigner) |
| RaiseResizeEvent() |
Obsolete.
Raises the OnControlResize() event. |
| RegisterClone(Object, Object) |
Registers internal data in a cloned control. |
| SetEditableDesignerRegionContent(EditableDesignerRegion, String) |
Specifies the content for an editable region of the control at design time. |
| SetRegionContent(EditableDesignerRegion, String) |
Specifies the content for an editable region in the design-time view of the control. |
| SetViewFlags(ViewFlags, Boolean) |
Assigns the specified bitwise ViewFlags enumeration to the specified flag value. |
| ToString() |
Returns a string that represents the current object. (Inherited from Object) |
| UpdateDesignTimeHtml() |
Refreshes the design-time HTML markup for the associated Web server control by calling the GetDesignTimeHtml method. |
