ConfigurationPropertyAttribute 类

定义

以声明方式指示 .NET 实例化配置属性。 此类不能被继承。

public ref class ConfigurationPropertyAttribute sealed : Attribute
[System.AttributeUsage(System.AttributeTargets.Property)]
public sealed class ConfigurationPropertyAttribute : Attribute
[<System.AttributeUsage(System.AttributeTargets.Property)>]
type ConfigurationPropertyAttribute = class
    inherit Attribute
Public NotInheritable Class ConfigurationPropertyAttribute
Inherits Attribute
继承
ConfigurationPropertyAttribute
属性

示例

以下示例演示如何使用 ConfigurationPropertyAttribute 特性定义自定义ConfigurationSection对象的属性。

该示例包含两个类。 自定义 UrlsSection 类使用 ConfigurationPropertyAttribute 来定义其自己的属性。 类 UsingConfigurationPropertyAttribute 使用 UrlsSection 读取和写入应用程序配置文件中的自定义节。

using System;
using System.Configuration;

// Define a custom section.
// This class shows how to use the ConfigurationPropertyAttribute.
public class UrlsSection : ConfigurationSection
{
    [ConfigurationProperty("name", DefaultValue = "Contoso",
        IsRequired = true, IsKey = true)]
    public string Name
    {
        get
        {
            return (string)this["name"];
        }
        set
        {
            this["name"] = value;
        }
    }

    [ConfigurationProperty("url", DefaultValue = "http://www.contoso.com",
        IsRequired = true)]
    [RegexStringValidator(@"\w+:\/\/[\w.]+\S*")]
    public string Url
    {
        get
        {
            return (string)this["url"];
        }
        set
        {
            this["url"] = value;
        }
    }

    [ConfigurationProperty("port", DefaultValue = (int)0, IsRequired = false)]
    [IntegerValidator(MinValue = 0, MaxValue = 8080, ExcludeRange = false)]
    public int Port
    {
        get
        {
            return (int)this["port"];
        }
        set
        {
            this["port"] = value;
        }
    }
}
Imports System.Configuration


' Define a custom section.
' This class shows how to use the ConfigurationPropertyAttribute.
Public Class UrlsSection
    Inherits ConfigurationSection
    <ConfigurationProperty("name", DefaultValue:="Contoso", IsRequired:=True, IsKey:=True)>
    Public Property Name() As String
        Get
            Return CStr(Me("name"))
        End Get
        Set(ByVal value As String)
            Me("name") = value
        End Set
    End Property

    <ConfigurationProperty("url", DefaultValue:="http://www.contoso.com", IsRequired:=True), RegexStringValidator("\w+:\/\/[\w.]+\S*")>
    Public Property Url() As String
        Get
            Return CStr(Me("url"))
        End Get
        Set(ByVal value As String)
            Me("url") = value
        End Set
    End Property

    <ConfigurationProperty("port", DefaultValue:=0, IsRequired:=False), IntegerValidator(MinValue:=0, MaxValue:=8080, ExcludeRange:=False)>
    Public Property Port() As Integer
        Get
            Return CInt(Fix(Me("port")))
        End Get
        Set(ByVal value As Integer)
            Me("port") = value
        End Set
    End Property
End Class
using System;
using System.Configuration;

public class UsingConfigurationPropertyAttribute
{

    // Create a custom section and save it in the 
    // application configuration file.
    static void CreateCustomSection()
    {
        try
        {

            // Create a custom configuration section.
            UrlsSection customSection = new UrlsSection();

            // Get the current configuration file.
            System.Configuration.Configuration config =
                    ConfigurationManager.OpenExeConfiguration(
                    ConfigurationUserLevel.None);

            // Add the custom section to the application
            // configuration file.
            if (config.Sections["CustomSection"] == null)
            {
                config.Sections.Add("CustomSection", customSection);
            }

            // Save the application configuration file.
            customSection.SectionInformation.ForceSave = true;
            config.Save(ConfigurationSaveMode.Modified);

            Console.WriteLine("Created custom section in the application configuration file: {0}",
                config.FilePath);
            Console.WriteLine();
        }
        catch (ConfigurationErrorsException err)
        {
            Console.WriteLine("CreateCustomSection: {0}", err.ToString());
        }
    }

    static void ReadCustomSection()
    {
        try
        {
            // Get the application configuration file.
            System.Configuration.Configuration config =
                    ConfigurationManager.OpenExeConfiguration(
                    ConfigurationUserLevel.None) as Configuration;

            // Read and display the custom section.
            UrlsSection customSection =
                config.GetSection("CustomSection") as UrlsSection;
            Console.WriteLine("Reading custom section from the configuration file.");
            Console.WriteLine("Section name: {0}", customSection.Name);
            Console.WriteLine("Url: {0}", customSection.Url);
            Console.WriteLine("Port: {0}", customSection.Port);
            Console.WriteLine();
        }
        catch (ConfigurationErrorsException err)
        {
            Console.WriteLine("ReadCustomSection(string): {0}", err.ToString());
        }
    }
    
    static void Main(string[] args)
    {
       
        // Get the name of the application.
        string appName =
            Environment.GetCommandLineArgs()[0];

        // Create a custom section and save it in the 
        // application configuration file.
        CreateCustomSection();

        // Read the custom section saved in the
        // application configuration file.
        ReadCustomSection();

        Console.WriteLine("Press enter to exit.");

        Console.ReadLine();
    }
}
Imports System.Configuration

Public Class UsingConfigurationPropertyAttribute

    ' Create a custom section and save it in the 
    ' application configuration file.
    Private Shared Sub CreateCustomSection()
        Try

            ' Create a custom configuration section.
            Dim customSection As New UrlsSection()

            ' Get the current configuration file.
            Dim config As System.Configuration.Configuration = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None)

            ' Add the custom section to the application
            ' configuration file.
            If config.Sections("CustomSection") Is Nothing Then
                config.Sections.Add("CustomSection", customSection)
            End If


            ' Save the application configuration file.
            customSection.SectionInformation.ForceSave = True
            config.Save(ConfigurationSaveMode.Modified)

            Console.WriteLine("Created custom section in the application configuration file: {0}", config.FilePath)
            Console.WriteLine()

        Catch err As ConfigurationErrorsException
            Console.WriteLine("CreateCustomSection: {0}", err.ToString())
        End Try

    End Sub

    Private Shared Sub ReadCustomSection()
        Try
            ' Get the application configuration file.
            Dim config As System.Configuration.Configuration = TryCast(ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None), Configuration)

            ' Read and display the custom section.
            Dim customSection As UrlsSection = TryCast(config.GetSection("CustomSection"), UrlsSection)
            Console.WriteLine("Reading custom section from the configuration file.")
            Console.WriteLine("Section name: {0}", customSection.Name)
            Console.WriteLine("Url: {0}", customSection.Url)
            Console.WriteLine("Port: {0}", customSection.Port)
            Console.WriteLine()
        Catch err As ConfigurationErrorsException
            Console.WriteLine("ReadCustomSection(string): {0}", err.ToString())
        End Try

    End Sub

    Shared Sub Main(ByVal args() As String)

        ' Get the name of the application.
        Dim appName As String = Environment.GetCommandLineArgs()(0)

        ' Create a custom section and save it in the 
        ' application configuration file.
        CreateCustomSection()

        ' Read the custom section saved in the
        ' application configuration file.
        ReadCustomSection()

        Console.WriteLine("Press enter to exit.")

        Console.ReadLine()
    End Sub
End Class

下面是配置文件的摘录,其中包含上一示例中定义的自定义节。

<?xml version="1.0" encoding="utf-8"?>  
<configuration>  
    <configSections>  
        <section name="CustomSection" type="UrlsSection, UsingConfigurationPropertyAttribute, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null" />  
    </configSections>  
    <CustomSection name="Contoso" url="http://www.contoso.com" />  
</configuration>  

注解

使用 ConfigurationPropertyAttribute 来修饰配置属性,这将指示 .NET 实例化并使用修饰参数的值初始化属性。

注意

创建自定义配置元素的最简单方法是使用特性化 (声明性) 模型。 声明自定义公共属性并使用 属性修饰它们 ConfigurationPropertyAttribute 。 对于使用此属性标记的每个属性,.NET 使用反射来读取修饰参数并创建相关 ConfigurationProperty 实例。 还可以使用编程模型,在这种情况下,由你负责声明自定义公共属性并返回其集合。

.NET 配置系统提供可在创建自定义配置元素期间使用的属性类型。 有两种类型的属性类型:

  1. 指示 .NET 如何实例化自定义配置元素属性的类型。 这些类型包括:

  2. 指示 .NET 如何验证自定义配置元素属性的类型。 这些类型包括:

构造函数

ConfigurationPropertyAttribute(String)

初始化 ConfigurationPropertyAttribute 类的新实例。

属性

DefaultValue

获取或设置修饰属性的默认值。

IsDefaultCollection

获取或设置一个值,指示此属性集合是否为经过修饰的配置属性的默认属性集合。

IsKey

获取或设置一个值,该值指示此属性是否是该经过修饰的元素属性的 Key 属性。

IsRequired

获取或设置一个值,该值指示经过修饰的元素属性是否为必需。

Name

获取经过修饰的配置元素属性的名称。

Options

为经过修饰的配置元素属性获取或设置 ConfigurationPropertyOptions

TypeId

在派生类中实现时,获取此 Attribute 的唯一标识符。

(继承自 Attribute)

方法

Equals(Object)

返回一个值,该值指示此实例是否与指定的对象相等。

(继承自 Attribute)
GetHashCode()

返回此实例的哈希代码。

(继承自 Attribute)
GetType()

获取当前实例的 Type

(继承自 Object)
IsDefaultAttribute()

在派生类中重写时,指示此实例的值是否是派生类的默认值。

(继承自 Attribute)
Match(Object)

当在派生类中重写时,返回一个指示此实例是否等于指定对象的值。

(继承自 Attribute)
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)

显式接口实现

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

将一组名称映射为对应的一组调度标识符。

(继承自 Attribute)
_Attribute.GetTypeInfo(UInt32, UInt32, IntPtr)

检索对象的类型信息,然后可以使用该信息获取接口的类型信息。

(继承自 Attribute)
_Attribute.GetTypeInfoCount(UInt32)

检索对象提供的类型信息接口的数量(0 或 1)。

(继承自 Attribute)
_Attribute.Invoke(UInt32, Guid, UInt32, Int16, IntPtr, IntPtr, IntPtr, IntPtr)

提供对某一对象公开的属性和方法的访问。

(继承自 Attribute)

适用于

另请参阅