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DesignerAutoFormatCollection Class

Definition

Represents a collection of DesignerAutoFormat objects within a control designer. This class cannot be inherited.

public ref class DesignerAutoFormatCollection sealed : System::Collections::IList
public sealed class DesignerAutoFormatCollection : System.Collections.IList
type DesignerAutoFormatCollection = class
    interface IList
    interface ICollection
    interface IEnumerable
Public NotInheritable Class DesignerAutoFormatCollection
Implements IList
Inheritance
DesignerAutoFormatCollection
Implements

Examples

The following code example demonstrates how to implement the AutoFormats property 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

The ControlDesigner class and any derived class defines the AutoFormats property as a DesignerAutoFormatCollection object. Control developers can override the AutoFormats property in a derived control designer, add custom automatic formatting styles, and return the collection of supported formats to the visual designer.

The collection dynamically increases as objects are added. Indexes in this collection are zero-based. Use the Count property to determine how many automatic style formats are in the collection.

Additionally, use the DesignerAutoFormatCollection methods and properties to provide the following functionality:

  • The Add method to add a single format to the collection.

  • The Insert method to add a format at a particular index within the collection.

  • The Remove method to remove a format.

  • The RemoveAt method to remove the format at a particular index.

  • The Contains method to determine whether a particular format is already in the collection.

  • The IndexOf method to retrieve the index of a format within the collection.

  • The Item[] property to get or set the format at a particular index, using array notation.

  • The Clear method to remove all formats from the collection.

  • The Count property to determine the number of formats in the collection.

  • The IndexOf method to get the position of a format within the collection.

Constructors

DesignerAutoFormatCollection()

Initializes a new instance of the DesignerAutoFormatCollection class.

Properties

Count

Gets the number of DesignerAutoFormat objects in the collection.

Item[Int32]

Gets or sets a DesignerAutoFormat object at the specified index in the collection.

PreviewSize

Gets the maximum outer dimensions of the control as it will appear at run time.

SyncRoot

Gets an object that can be used to synchronize access to the DesignerAutoFormatCollection object.

Methods

Add(DesignerAutoFormat)

Adds the specified DesignerAutoFormat object to the end of the collection.

Clear()

Removes all formats from the collection.

Contains(DesignerAutoFormat)

Determines whether the specified format is contained within the collection.

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)
GetType()

Gets the Type of the current instance.

(Inherited from Object)
IndexOf(DesignerAutoFormat)

Returns the index of the specified DesignerAutoFormat object within the collection.

Insert(Int32, DesignerAutoFormat)

Inserts a DesignerAutoFormat object into the collection at the specified index.

MemberwiseClone()

Creates a shallow copy of the current Object.

(Inherited from Object)
Remove(DesignerAutoFormat)

Removes the specified DesignerAutoFormat object from the collection.

RemoveAt(Int32)

Removes the DesignerAutoFormat object at the specified index within the collection.

ToString()

Returns a string that represents the current object.

(Inherited from Object)

Explicit Interface Implementations

ICollection.CopyTo(Array, Int32)

Copies the elements of the collection to an Array object, starting at a particular Array index when the DesignerAutoFormatCollection object is cast to an ICollection interface.

ICollection.Count

Gets the number of elements that are contained in the collection when the DesignerAutoFormatCollection object is cast to an ICollection interface.

ICollection.IsSynchronized

Gets a value that indicates whether access to the collection is synchronized (thread safe) when the DesignerAutoFormatCollection object is cast to an ICollection interface.

IEnumerable.GetEnumerator()

Returns an IEnumerator interface that iterates through the collection when the DesignerAutoFormatCollection object is cast to an IEnumerable interface.

IList.Add(Object)

Adds an item to the collection when the DesignerAutoFormatCollection object is cast to an IList interface.

IList.Contains(Object)

Determines whether the collection contains a specific value when the DesignerAutoFormatCollection object is cast to an IList interface.

IList.IndexOf(Object)

Determines the index of a specific item in the collection when the DesignerAutoFormatCollection object is cast to an IList interface.

IList.Insert(Int32, Object)

Inserts an item into the collection at the specified index when the DesignerAutoFormatCollection object is cast to an IList interface.

IList.IsFixedSize

Gets a value that indicates whether the collection has a fixed size when the DesignerAutoFormatCollection object is cast to an IList interface.

IList.IsReadOnly

For a description of this method, see IsReadOnly.

IList.Item[Int32]

Gets the element at the specified index when the DesignerAutoFormatCollection object is cast to an IList interface.

IList.Remove(Object)

Removes the first occurrence of a specific object from the collection when the DesignerAutoFormatCollection object is cast to an IList interface.

IList.RemoveAt(Int32)

Removes the item at the specified index when the DesignerAutoFormatCollection object is cast to an IList interface.

Extension Methods

Cast<TResult>(IEnumerable)

Casts the elements of an IEnumerable to the specified type.

OfType<TResult>(IEnumerable)

Filters the elements of an IEnumerable based on a specified type.

AsParallel(IEnumerable)

Enables parallelization of a query.

AsQueryable(IEnumerable)

Converts an IEnumerable to an IQueryable.

Applies to

See also