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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.

System.Object
  System.Attribute
    System.ComponentModel.NotifyParentPropertyAttribute

Namespace:  System.ComponentModel
Assembly:  System (in System.dll)
[AttributeUsageAttribute(AttributeTargets.Property)]
public sealed class NotifyParentPropertyAttribute : Attribute

The NotifyParentPropertyAttribute type exposes the following members.

  Name Description
Public method NotifyParentPropertyAttribute 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.
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  Name Description
Public property NotifyParent Gets or sets a value indicating whether the parent property should be notified of changes to the value of the property.
Public property TypeId When implemented in a derived class, gets a unique identifier for this Attribute. (Inherited from Attribute.)
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  Name Description
Public method Equals Gets a value indicating whether the specified object is the same as the current object. (Overrides Attribute.Equals(Object).)
Protected method Finalize Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
Public method GetHashCode Gets the hash code for this object. (Overrides Attribute.GetHashCode().)
Public method GetType Gets the Type of the current instance. (Inherited from Object.)
Public method IsDefaultAttribute Gets a value indicating whether the current value of the attribute is the default value for the attribute. (Overrides Attribute.IsDefaultAttribute().)
Public method Match When overridden in a derived class, returns a value that indicates whether this instance equals a specified object. (Inherited from Attribute.)
Protected method MemberwiseClone Creates a shallow copy of the current Object. (Inherited from Object.)
Public method ToString Returns a string that represents the current object. (Inherited from Object.)
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  Name Description
Public field Static member Default Indicates the default attribute state, that the property should not notify the parent property of changes to its value. This field is read-only.
Public field Static member No Indicates that the parent property is not be notified of changes to the value of the property. This field is read-only.
Public field Static member Yes Indicates that the parent property is notified of changes to the value of the property. This field is read-only.
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  Name Description
Explicit interface implemetation Private method _Attribute.GetIDsOfNames Maps a set of names to a corresponding set of dispatch identifiers. (Inherited from Attribute.)
Explicit interface implemetation Private method _Attribute.GetTypeInfo Retrieves the type information for an object, which can be used to get the type information for an interface. (Inherited from Attribute.)
Explicit interface implemetation Private method _Attribute.GetTypeInfoCount Retrieves the number of type information interfaces that an object provides (either 0 or 1). (Inherited from Attribute.)
Explicit interface implemetation Private method _Attribute.Invoke Provides access to properties and methods exposed by an object. (Inherited from Attribute.)
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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.


using System;
using System.ComponentModel;
using System.Drawing;
using System.Globalization;
using System.Windows.Forms;

namespace ExpandableObjectDemo
{
    public partial class DemoControl : UserControl
    {
        BorderAppearance borderAppearanceValue = new BorderAppearance();
        private System.ComponentModel.IContainer components = null;

        public DemoControl()
        {
            InitializeComponent();
        }

        protected override void Dispose(bool disposing)
        {
            if (disposing && (components != null))
            {
                components.Dispose();
            }
            base.Dispose(disposing);
        }

        [Browsable(true)]
        [EditorBrowsable(EditorBrowsableState.Always)]
        [Category("Demo")]
        [DesignerSerializationVisibility(DesignerSerializationVisibility.Content)]
        public BorderAppearance Border
        {
            get
            {
                return this.borderAppearanceValue;
            }

            set
            {
                this.borderAppearanceValue = value;
            }
        }

        private void InitializeComponent()
        {
            components = new System.ComponentModel.Container();
            this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
        }
    }

    [TypeConverter(typeof(BorderAppearanceConverter))]
    public class BorderAppearance
    {
        private int borderSizeValue = 1;
        private Color borderColorValue = Color.Empty;

        [Browsable(true),
        NotifyParentProperty(true),
        EditorBrowsable(EditorBrowsableState.Always),
        DefaultValue(1)]
        public int BorderSize
        {
            get
            {
                return borderSizeValue;
            }
            set
            {
                if (value < 0)
                {
                    throw new ArgumentOutOfRangeException(
                        "BorderSize",
                        value,
                        "must be >= 0");
                }

                if (borderSizeValue != value)
                {
                    borderSizeValue = value;
                }
            }
        }

        [Browsable(true)]
        [NotifyParentProperty(true)]
        [EditorBrowsable(EditorBrowsableState.Always)]
        [DefaultValue(typeof(Color), "")]
        public Color BorderColor
        {
            get
            {
                return borderColorValue;
            }
            set
            {
                if (value.Equals(Color.Transparent))
                {
                    throw new NotSupportedException("Transparent colors are not supported.");
                }

                if (borderColorValue != value)
                {
                    borderColorValue = value;
                }
            }
        }
    }

    public class BorderAppearanceConverter : ExpandableObjectConverter
    {
        // This override prevents the PropertyGrid from 
        // displaying the full type name in the value cell.
        public override object ConvertTo(
            ITypeDescriptorContext context,
            CultureInfo culture,
            object value,
            Type destinationType)
        {
            if (destinationType == typeof(string))
            {
                return "";
            }

            return base.ConvertTo(
                context,
                culture,
                value,
                destinationType);
        }
    }
}


.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
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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