DesignerAutoFormat 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 the abstract base class for creating formats that can be applied to a custom Web server control at design time.
public ref class DesignerAutoFormat abstractpublic abstract class DesignerAutoFormattype DesignerAutoFormat = classPublic MustInherit Class DesignerAutoFormat- Inheritance
-
DesignerAutoFormat
Examples
The following code example demonstrates how to implement automatic formatting in a custom control designer. The derived control designer implements the AutoFormats property by adding three instances of a custom automatic format that are derived from the DesignerAutoFormat class.
using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Web.UI;
using System.Web.UI.Design;
using System.Web.UI.Design.WebControls;
using System.Web.UI.WebControls;
namespace CustomControls.Design.CS
{
// A custom Label control whose contents can be indented
[Designer(typeof(IndentLabelDesigner)),
ToolboxData("<{0}:IndentLabel Runat=\"server\"></{0}:IndentLabel>")]
public class IndentLabel : Label
{
private int _indent = 0;
// Property to indent all text within the label
[Category("Appearance"), DefaultValue(0),
PersistenceMode(PersistenceMode.Attribute)]
public int Indent
{
get { return _indent; }
set
{
_indent = value;
// Get the number of pixels to indent
int ind = value * 8;
// Add the indent style to the control
if (ind > 0)
this.Style.Add(HtmlTextWriterStyle.MarginLeft, ind.ToString() + "px");
else
this.Style.Remove(HtmlTextWriterStyle.MarginLeft);
}
}
}
// A design-time ControlDesigner for the IndentLabel control
[SupportsPreviewControl(true)]
public class IndentLabelDesigner : LabelDesigner
{
private DesignerAutoFormatCollection _autoFormats = null;
// The collection of AutoFormat objects for the IndentLabel object
public override DesignerAutoFormatCollection AutoFormats
{
get
{
if (_autoFormats == null)
{
// Create the collection
_autoFormats = new DesignerAutoFormatCollection();
// Create and add each AutoFormat object
_autoFormats.Add(new IndentLabelAutoFormat("MyClassic"));
_autoFormats.Add(new IndentLabelAutoFormat("MyBright"));
_autoFormats.Add(new IndentLabelAutoFormat("Default"));
}
return _autoFormats;
}
}
// An AutoFormat object for the IndentLabel control
private class IndentLabelAutoFormat : DesignerAutoFormat
{
public IndentLabelAutoFormat(string name) : base(name)
{ }
// Applies styles based on the Name of the AutoFormat
public override void Apply(Control inLabel)
{
if (inLabel is IndentLabel)
{
IndentLabel ctl = (IndentLabel)inLabel;
// Apply formatting according to the Name
if (this.Name == "MyClassic")
{
// For MyClassic, apply style elements directly to the control
ctl.ForeColor = Color.Gray;
ctl.BackColor = Color.LightGray;
ctl.Font.Size = FontUnit.XSmall;
ctl.Font.Name = "Verdana,Geneva,Sans-Serif";
}
else if (this.Name == "MyBright")
{
// For MyBright, apply style elements to the Style property
this.Style.ForeColor = Color.Maroon;
this.Style.BackColor = Color.Yellow;
this.Style.Font.Size = FontUnit.Medium;
// Merge the AutoFormat style with the control's style
ctl.MergeStyle(this.Style);
}
else
{
// For the Default format, apply style elements to the control
ctl.ForeColor = Color.Black;
ctl.BackColor = Color.Empty;
ctl.Font.Size = FontUnit.XSmall;
}
}
}
}
}
}
Imports System.Drawing
Imports System.Collections
Imports System.ComponentModel
Imports System.Web.UI
Imports System.Web.UI.Design
Imports System.Web.UI.Design.WebControls
Imports System.Web.UI.WebControls
Namespace CustomControls.Design
' A custom Label control whose contents can be indented
<Designer(GetType(IndentLabelDesigner)), _
ToolboxData("<{0}:IndentLabel Runat=""server""></{0}:IndentLabel>")> _
Public Class IndentLabel
Inherits System.Web.UI.WebControls.Label
Dim _indent As Integer = 0
<Category("Appearance"), DefaultValue(0), _
PersistenceMode(PersistenceMode.Attribute)> _
Property Indent() As Integer
Get
Return _indent
End Get
Set(ByVal Value As Integer)
_indent = Value
' Get the number of pixels to indent
Dim ind As Integer = _indent * 8
' Add the indent style to the control
If ind > 0 Then
Me.Style.Add(HtmlTextWriterStyle.MarginLeft, ind.ToString() & "px")
Else
Me.Style.Remove(HtmlTextWriterStyle.MarginLeft)
End If
End Set
End Property
End Class
' A design-time ControlDesigner for the IndentLabel control
Public Class IndentLabelDesigner
Inherits LabelDesigner
Private _autoFormats As DesignerAutoFormatCollection = Nothing
' The collection of AutoFormat objects for the IndentLabel object
Public Overrides ReadOnly Property AutoFormats() As DesignerAutoFormatCollection
Get
If _autoFormats Is Nothing Then
' Create the collection
_autoFormats = New DesignerAutoFormatCollection()
' Create and add each AutoFormat object
_autoFormats.Add(New IndentLabelAutoFormat("MyClassic"))
_autoFormats.Add(New IndentLabelAutoFormat("MyBright"))
_autoFormats.Add(New IndentLabelAutoFormat("Default"))
End If
Return _autoFormats
End Get
End Property
' An AutoFormat object for the IndentLabel control
Public Class IndentLabelAutoFormat
Inherits DesignerAutoFormat
Public Sub New(ByVal name As String)
MyBase.New(name)
End Sub
' Applies styles based on the Name of the AutoFormat
Public Overrides Sub Apply(ByVal inLabel As Control)
If TypeOf inLabel Is IndentLabel Then
Dim ctl As IndentLabel = CType(inLabel, IndentLabel)
' Apply formatting according to the Name
If Me.Name.Equals("MyClassic") Then
' For MyClassic, apply style elements directly to the control
ctl.ForeColor = Color.Gray
ctl.BackColor = Color.LightGray
ctl.Font.Size = FontUnit.XSmall
ctl.Font.Name = "Verdana,Geneva,Sans-Serif"
ElseIf Me.Name.Equals("MyBright") Then
' For MyBright, apply style elements to the Style object
Me.Style.ForeColor = Color.Maroon
Me.Style.BackColor = Color.Yellow
Me.Style.Font.Size = FontUnit.Medium
' Merge the AutoFormat style with the control's style
ctl.MergeStyle(Me.Style)
Else
' For the Default format, apply style elements to the control
ctl.ForeColor = Color.Black
ctl.BackColor = Color.Empty
ctl.Font.Size = FontUnit.XSmall
End If
End If
End Sub
End Class
End Class
End Namespace
Remarks
DesignerAutoFormat provides a base class that can be inherited from and extended to display a formatted custom Web server control at design time in a visual designer tool such as Visual Studio 2005.
A control developer provides automatic formatting in order to help developers who use the control to select a preferred display. A custom DesignerAutoFormat object works with a custom control designer to provide automatic formatting at design time for a custom control. For example, the Calendar control provides a variety of formats that can be applied by a developer at design time.
To implement automatic formatting for a custom control:
Create the custom control.
Derive a designer class from the ControlDesigner class or another designer class that is appropriate for your control, such as the TextControlDesigner.
Derive a format class from the DesignerAutoFormat class that formats your custom control by overriding the Apply method.
In your designer class, populate the AutoFormats property, which is a DesignerAutoFormatCollection object, with one instance of your format class for each named format that your designer can apply.
The DesignerAutoFormat class provides the following members to support automatic formatting at design time:
The Apply method, which applies the named format to the specified control.
The GetPreviewControl method, which provides a copy of the control for previewing in an AutoFormat dialog box of a visual designer such as Visual Studio 2005.
The Name property, which provides the text to display in a list of formats in a visual designer.
Notes to Implementers
When you inherit from the DesignerAutoFormat class, you must override the Apply(Control) method to preview a formatted control and to apply the selected format to your control.
Constructors
| DesignerAutoFormat(String) |
Initializes a new instance of the DesignerAutoFormat class. |
Properties
| Name |
Gets the name of a DesignerAutoFormat object. |
| Style |
Gets a DesignerAutoFormatStyle object that is used by the DesignerAutoFormat object to render a design-time preview of the associated control. |
Methods
| Apply(Control) |
Applies the associated formatting to the specified control. |
| Equals(Object) |
Determines whether the specified object is equal to the current object. (Inherited from Object) |
| GetHashCode() |
Serves as the default hash function. (Inherited from Object) |
| GetPreviewControl(Control) |
Returns a copy of the associated control in order to provide a preview before applying the format to the control. |
| GetType() |
Gets the Type of the current instance. (Inherited from Object) |
| MemberwiseClone() |
Creates a shallow copy of the current Object. (Inherited from Object) |
| ToString() |
Returns a string that represents the current DesignerAutoFormat object. |
