NotifyParentPropertyAttribute Class

 

Indicates that the parent property is notified when the value of the property that this attribute is applied to is modified. This class cannot be inherited.

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

System.Object
  System.Attribute
    System.ComponentModel.NotifyParentPropertyAttribute

<AttributeUsageAttribute(AttributeTargets.Property)>
Public NotInheritable Class NotifyParentPropertyAttribute
	Inherits Attribute

NameDescription
System_CAPS_pubmethodNotifyParentPropertyAttribute(Boolean)

Initializes a new instance of the NotifyParentPropertyAttribute class, using the specified value to determine whether the parent property is notified of changes to the value of the property.

NameDescription
System_CAPS_pubpropertyNotifyParent

Gets or sets a value indicating whether the parent property should be notified of changes to the value of the property.

System_CAPS_pubpropertyTypeId

When implemented in a derived class, gets a unique identifier for this Attribute.(Inherited from Attribute.)

NameDescription
System_CAPS_pubmethodEquals(Object)

Gets a value indicating whether the specified object is the same as the current object.(Overrides Attribute.Equals(Object).)

System_CAPS_pubmethodGetHashCode()

Gets the hash code for this object.(Overrides Attribute.GetHashCode().)

System_CAPS_pubmethodGetType()

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

System_CAPS_pubmethodIsDefaultAttribute()

Gets a value indicating whether the current value of the attribute is the default value for the attribute.(Overrides Attribute.IsDefaultAttribute().)

System_CAPS_pubmethodMatch(Object)

When overridden in a derived class, returns a value that indicates whether this instance equals a specified object.(Inherited from Attribute.)

System_CAPS_pubmethodToString()

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

NameDescription
System_CAPS_pubfieldSystem_CAPS_staticDefault

Indicates the default attribute state, that the property should not notify the parent property of changes to its value. This field is read-only.

System_CAPS_pubfieldSystem_CAPS_staticNo

Indicates that the parent property is not be notified of changes to the value of the property. This field is read-only.

System_CAPS_pubfieldSystem_CAPS_staticYes

Indicates that the parent property is notified of changes to the value of the property. This field is read-only.

NameDescription
System_CAPS_pubinterfaceSystem_CAPS_privmethod_Attribute.GetIDsOfNames(Guid, IntPtr, UInt32, UInt32, IntPtr)

Maps a set of names to a corresponding set of dispatch identifiers.(Inherited from Attribute.)

System_CAPS_pubinterfaceSystem_CAPS_privmethod_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.)

System_CAPS_pubinterfaceSystem_CAPS_privmethod_Attribute.GetTypeInfoCount(UInt32)

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

System_CAPS_pubinterfaceSystem_CAPS_privmethod_Attribute.Invoke(UInt32, Guid, UInt32, Int16, IntPtr, IntPtr, IntPtr, IntPtr)

Provides access to properties and methods exposed by an object.(Inherited from Attribute.)

Apply NotifyParentPropertyAttribute to a property if its parent property should receive notification of changes to the property's values. For example, in the Properties window, the DataGridView.RowTemplate property has nested properties such as Height and DefaultCellStyle. These nested properties are marked with NotifyParentPropertyAttribute(true) so they notify the parent property to update its value and display when the property values change.

For more information about using attributes, see Extending Metadata Using Attributes.

The following code example demonstrates how to use the NotifyParentPropertyAttribute and the ExpandableObjectConverter class to create an expandable property on a custom control.

Imports System
Imports System.ComponentModel
Imports System.Drawing
Imports System.Globalization
Imports System.Windows.Forms

Public Class DemoControl
    Inherits UserControl

    Private borderAppearanceValue As New BorderAppearance()
    Private components As System.ComponentModel.IContainer = Nothing


    Public Sub New()
        InitializeComponent()

    End Sub

    Protected Overrides Sub Dispose(ByVal disposing As Boolean)

        If disposing AndAlso (components IsNot Nothing) Then
            components.Dispose()
        End If

        MyBase.Dispose(disposing)

    End Sub

    <Browsable(True), _
    EditorBrowsable(EditorBrowsableState.Always), _
    Category("Demo"), _
    DesignerSerializationVisibility(DesignerSerializationVisibility.Content)> _
    Public Property Border() As BorderAppearance

        Get
            Return Me.borderAppearanceValue
        End Get

        Set(ByVal value As BorderAppearance)
            Me.borderAppearanceValue = value
        End Set

    End Property

    Private Sub InitializeComponent()
        components = New System.ComponentModel.Container()
        Me.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font

    End Sub
End Class

<TypeConverter(GetType(BorderAppearanceConverter))>  _
Public Class BorderAppearance
    Private borderSizeValue As Integer = 1
    Private borderColorValue As Color = Color.Empty


    <Browsable(True), NotifyParentProperty(True), EditorBrowsable(EditorBrowsableState.Always), DefaultValue(1)>  _
    Public Property BorderSize() As Integer 
        Get
            Return borderSizeValue
        End Get
        Set
            If value < 0 Then
                Throw New ArgumentOutOfRangeException("BorderSize", value, "must be >= 0")
            End If

            If borderSizeValue <> value Then
                borderSizeValue = value
            End If
        End Set
    End Property


    <Browsable(True), NotifyParentProperty(True), EditorBrowsable(EditorBrowsableState.Always), DefaultValue(GetType(Color), "")>  _
    Public Property BorderColor() As Color 
        Get
            Return borderColorValue
        End Get
        Set
            If value.Equals(Color.Transparent) Then
                Throw New NotSupportedException("Transparent colors are not supported.")
            End If

            If borderColorValue <> value Then
                borderColorValue = value
            End If
        End Set
    End Property
End Class

Public Class BorderAppearanceConverter
    Inherits ExpandableObjectConverter

    ' This override prevents the PropertyGrid from 
    ' displaying the full type name in the value cell.
    Public Overrides Function ConvertTo(ByVal context As ITypeDescriptorContext, ByVal culture As CultureInfo, ByVal value As Object, ByVal destinationType As Type) As Object

        If destinationType Is GetType(String) Then
            Return ""
        End If

        Return MyBase.ConvertTo(context, culture, value, destinationType)

    End Function
End Class

.NET Framework
Available since 1.1

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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