AttributeTable 类

项目
05/28/2012

[本文档仅供预览，在以后的发行版中可能会发生更改。包含的空白主题用作占位符。]

用于定义设计时外观和行为的元数据特性表。

继承层次结构

System.Object
Microsoft.Windows.Design.Metadata.AttributeTable

命名空间： Microsoft.Windows.Design.Metadata
程序集： Microsoft.Windows.Design.Extensibility（在 Microsoft.Windows.Design.Extensibility.dll 中）

语法

声明
Public NotInheritable Class AttributeTable

public sealed class AttributeTable

public ref class AttributeTable sealed

[<Sealed>]
type AttributeTable =  class end

public final class AttributeTable

AttributeTable 类型公开以下成员。

属性

	名称	说明
	AttributedTypes	获取具有某些形式的特性重写（例如对属性或类型本身的重写）的所有类型的枚举。

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方法

	名称	说明
	ContainsAttributes	返回一个值，该值指示此表是否包含指定类型的任何元数据。
	Equals	确定指定的 Object 是否等于当前的 Object。（继承自 Object。）
	Finalize	允许对象在“垃圾回收”回收之前尝试释放资源并执行其他清理操作。（继承自 Object。）
	GetCustomAttributes(Assembly)	返回提供给指定的程序集的所有特性的枚举。
	GetCustomAttributes(Type)	返回提供给指定类型的所有特性的枚举。
	GetCustomAttributes(Type, String)	返回提供给指定的类型和成员名称的所有特性的枚举。
	GetHashCode	用作特定类型的哈希函数。（继承自 Object。）
	GetType	获取当前实例的 Type。（继承自 Object。）
	MemberwiseClone	创建当前 Object 的浅表副本。（继承自 Object。）
	ToString	返回表示当前对象的字符串。（继承自 Object。）

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备注

使用 AttributeTable 类将设计时元数据特性与 Windows Presentation Foundation (WPF) 类型关联。

若要创建特性表，请调用 AttributeTableBuilder 类的 CreateTable 方法。有关更多信息，请参见提供设计时元数据。

特性表实际上是一个只读字典，但其键和值分别进行计算。如果特性表包含特定类型的特性，则查询该特性表将非常高效。实际的特性集是按需创建的。

示例

下面的代码示例演示如何创建和填充特性表。有关更多信息，请参见演练：创建设计时装饰器。

Imports System
Imports System.Collections
Imports System.Collections.Generic
Imports System.ComponentModel
Imports System.Reflection
Imports System.Text
Imports System.Windows.Media
Imports System.Windows.Controls
Imports System.Windows

Imports Microsoft.Windows.Design
Imports Microsoft.Windows.Design.Features
Imports Microsoft.Windows.Design.Metadata

' The ProvideMetadata assembly-level attribute indicates to designers
' that this assembly contains a class that provides an attribute table. 
<Assembly: ProvideMetadata(GetType(CustomControlLibrary.VisualStudio.Design.Metadata))> 

' Container for any general design-time metadata to initialize.
' Designers look for a type in the design-time assembly that 
' implements IProvideAttributeTable. If found, designers instantiate
' this class and access its AttributeTable property automatically.
Friend Class Metadata
    Implements IProvideAttributeTable

    ' Accessed by the designer to register any design-time metadata.
    Public ReadOnly Property AttributeTable() As AttributeTable _
        Implements IProvideAttributeTable.AttributeTable
        Get
            Dim builder As New AttributeTableBuilder()

            ' Apply the ReadOnlyAttribute to the Background property 
            ' of the Button class.
            builder.AddCustomAttributes(GetType(Button), "Background", New ReadOnlyAttribute(True))

            Dim attributes As AttributeTable = builder.CreateTable()

            Dim hasCustomAttributes As Boolean = attributes.ContainsAttributes(GetType(Button))

            Dim types As IEnumerable(Of Type) = attributes.AttributedTypes

            ' The following code shows how to retrieve custom attributes
            ' using the GetCustomAttributes method overloads.
            Dim attrs0 As IEnumerable = attributes.GetCustomAttributes(GetType(Button))

            Dim attrs1 As IEnumerable = attributes.GetCustomAttributes(GetType(Button), "Background")

            Return attributes
        End Get
    End Property
End Class

using System;
using System.Collections;
using System.Collections.Generic;
using System.ComponentModel;
using System.Reflection;
using System.Text;
using System.Windows.Media;
using System.Windows.Controls;
using System.Windows;

using Microsoft.Windows.Design.Features;
using Microsoft.Windows.Design.Metadata;

// The ProvideMetadata assembly-level attribute indicates to designers
// that this assembly contains a class that provides an attribute table. 
[assembly: ProvideMetadata(typeof(CustomControlLibrary.VisualStudio.Design.Metadata))]
namespace CustomControlLibrary.VisualStudio.Design
{
    // Container for any general design-time metadata to initialize.
    // Designers look for a type in the design-time assembly that 
    // implements IProvideAttributeTable. If found, designers instantiate 
    // this class and access its AttributeTable property automatically.
    internal class Metadata : IProvideAttributeTable
    {
        // Accessed by the designer to register any design-time metadata.
        public AttributeTable AttributeTable
        {
            get
            {
                AttributeTableBuilder builder = new AttributeTableBuilder();

                // Apply the ReadOnlyAttribute to the Background property 
                // of the Button class.
                builder.AddCustomAttributes(
                    typeof(Button),
                    "Background",
                    new ReadOnlyAttribute(true));

                AttributeTable attributes = builder.CreateTable();

                bool hasCustomAttributes = attributes.ContainsAttributes(typeof(Button));

                IEnumerable<Type> types = attributes.AttributedTypes;

                // The following code shows how to retrieve custom attributes
                // using the GetCustomAttributes method overloads.
                IEnumerable attrs0 = attributes.GetCustomAttributes(typeof(Button));

                IEnumerable attrs1 = attributes.GetCustomAttributes(
                    typeof(Button),
                    "Background");

                return attributes;
            }
        }
    }
}

线程安全

此类型的任何公共 static（在 Visual Basic 中为 Shared）成员都是线程安全的。但不保证所有实例成员都是线程安全的。

请参见

参考

Microsoft.Windows.Design.Metadata 命名空间

AttributeTableBuilder

其他资源

提供设计时元数据