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ControlValuePropertyAttribute Class

Definition

Specifies the default property of a control that a ControlParameter object binds to at run time. This class cannot be inherited.

public ref class ControlValuePropertyAttribute sealed : Attribute
[System.AttributeUsage(System.AttributeTargets.Class)]
public sealed class ControlValuePropertyAttribute : Attribute
[<System.AttributeUsage(System.AttributeTargets.Class)>]
type ControlValuePropertyAttribute = class
    inherit Attribute
Public NotInheritable Class ControlValuePropertyAttribute
Inherits Attribute
Inheritance
ControlValuePropertyAttribute
Attributes

Examples

The following code example demonstrates how to apply a ControlValuePropertyAttribute attribute that specifies a default property and value to a custom control.


using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Text;
using System.Web.UI;
using System.Web.UI.WebControls;

namespace Samples.AspNet.CS.Controls
{
    // Set ControlValueProperty attribute to specify the default
    // property of this control that a ControlParameter object 
    // binds to at run time.
    [DefaultProperty("Text")]
    [ControlValueProperty("Text", "Default Text")]
    public class SimpleCustomControl : WebControl
    {
        private string text;

        [Bindable(true)]
        [Category("Appearance")]
        [DefaultValue("")]
        public string Text
        {
            get
            {
                return text;
            }
            set
            {
                text = value;
            }
        }

        protected override void Render(HtmlTextWriter output)
        {
            output.Write(Text);
        }
    }
}

Imports System.ComponentModel
Imports System.Web.UI

Namespace Samples.AspNet.VB.Controls

    ' Set ControlValueProperty attribute to specify the default
    ' property of this control that a ControlParameter object 
    ' binds to at run time.
    <DefaultProperty("Text"), ControlValueProperty("Text", "DefaultText")> Public Class SimpleCustomControl
        Inherits System.Web.UI.WebControls.WebControl

        Dim _text As String

        <Bindable(True), Category("Appearance"), DefaultValue("")> Property [Text]() As String
            Get
                Return _text
            End Get

            Set(ByVal Value As String)
                _text = Value
            End Set
        End Property

        Protected Overrides Sub Render(ByVal output As System.Web.UI.HtmlTextWriter)
            output.Write([Text])
        End Sub

    End Class

End Namespace

Remarks

When defining a ControlParameter object, you typically bind a control's property to a parameter by setting both the ControlID and PropertyName properties. If the PropertyName property is not set, a default property is used. The ControlValuePropertyAttribute attribute is applied to a control to specify its default property that a ControlParameter object binds to at run time.

For more information about using attributes, see Attributes.

For a list of initial property values for an instance of the ControlValuePropertyAttribute class, see the ControlValuePropertyAttribute constructor.

Constructors

ControlValuePropertyAttribute(String, Object)

Initializes a new instance of the ControlValuePropertyAttribute class using the specified property name and default value.

ControlValuePropertyAttribute(String, Type, String)

Initializes a new instance of the ControlValuePropertyAttribute class using the specified property name and default value. The default value is also converted to the specified data type.

ControlValuePropertyAttribute(String)

Initializes a new instance of the ControlValuePropertyAttribute class using the specified property name.

Properties

DefaultValue

Gets the default value for the default property of a control.

Name

Gets the default property for a control.

TypeId

When implemented in a derived class, gets a unique identifier for this Attribute.

(Inherited from Attribute)

Methods

Equals(Object)

Determines whether the current instance of the ControlValuePropertyAttribute object is equal to the specified object.

GetHashCode()

Returns the hash code for this instance.

GetType()

Gets the Type of the current instance.

(Inherited from Object)
IsDefaultAttribute()

When overridden in a derived class, indicates whether the value of this instance is the default value for the derived class.

(Inherited from Attribute)
Match(Object)

When overridden in a derived class, returns a value that indicates whether this instance equals a specified object.

(Inherited from Attribute)
MemberwiseClone()

Creates a shallow copy of the current Object.

(Inherited from Object)
ToString()

Returns a string that represents the current object.

(Inherited from Object)

Explicit Interface Implementations

_Attribute.GetIDsOfNames(Guid, IntPtr, UInt32, UInt32, IntPtr)

Maps a set of names to a corresponding set of dispatch identifiers.

(Inherited from Attribute)
_Attribute.GetTypeInfo(UInt32, UInt32, IntPtr)

Retrieves the type information for an object, which can be used to get the type information for an interface.

(Inherited from Attribute)
_Attribute.GetTypeInfoCount(UInt32)

Retrieves the number of type information interfaces that an object provides (either 0 or 1).

(Inherited from Attribute)
_Attribute.Invoke(UInt32, Guid, UInt32, Int16, IntPtr, IntPtr, IntPtr, IntPtr)

Provides access to properties and methods exposed by an object.

(Inherited from Attribute)

Applies to

See also