ConfigurationElement 类
定义
重要
一些信息与预发行产品相关，相应产品在发行之前可能会进行重大修改。 对于此处提供的信息，Microsoft 不作任何明示或暗示的担保。
表示配置文件中的配置元素。
public ref class ConfigurationElement abstractpublic abstract class ConfigurationElementtype ConfigurationElement = classPublic MustInherit Class ConfigurationElement- 继承
-
ConfigurationElement
- 派生
示例
下面的代码示例演示如何将自定义实现为自定义 ConfigurationElement 节中的单个元素，以及作为自定义节中的元素集合。 该示例由以下文件组成：
包含名为
MyUrls的自定义节的 app.config 文件。 本节包含一个简单元素， (它不包含) 的任何其他元素和元素集合。 简单元素命名simple为 ，集合名为urls。控制台应用程序。 应用程序读取 app.config 文件的内容，并将信息写入控制台。 它使用派生自 ConfigurationElement、 ConfigurationElementCollection和 ConfigurationSection的类。
派生自 类的名为
UrlsSection的 ConfigurationSection 类。 此类用于访问MyUrls配置文件中的 节。派生自 类的名为
UrlsCollection的 ConfigurationElementCollection 类。 此类用于访问urls配置文件中的 集合。派生自 类的名为
UrlConfigElement的 ConfigurationElement 类。 此类用于访问simple配置文件中的 元素和集合的成员urls。
若要运行该示例，请执行以下步骤：
创建具有控制台应用程序项目和名为
ConfigurationElement的类库项目的解决方案。将三个类文件放在类库项目中，并将其他文件放在控制台库项目中。
在这两个项目中都设置对 的
System.Configuration引用。在控制台应用程序项目中，设置对类库项目的项目引用。
// Set Assembly name to ConfigurationElement
using System;
using System.Configuration;
using System.Collections;
namespace Samples.AspNet
{
// Entry point for console application that reads the
// app.config file and writes to the console the
// URLs in the custom section.
class TestConfigurationElement
{
static void Main(string[] args)
{
// Get current configuration file.
System.Configuration.Configuration config =
ConfigurationManager.OpenExeConfiguration(
ConfigurationUserLevel.None);
// Get the MyUrls section.
UrlsSection myUrlsSection =
config.GetSection("MyUrls") as UrlsSection;
if (myUrlsSection == null)
{
Console.WriteLine("Failed to load UrlsSection.");
}
else
{
Console.WriteLine("The 'simple' element of app.config:");
Console.WriteLine(" Name={0} URL={1} Port={2}",
myUrlsSection.Simple.Name,
myUrlsSection.Simple.Url,
myUrlsSection.Simple.Port);
Console.WriteLine("The urls collection of app.config:");
for (int i = 0; i < myUrlsSection.Urls.Count; i++)
{
Console.WriteLine(" Name={0} URL={1} Port={2}",
myUrlsSection.Urls[i].Name,
myUrlsSection.Urls[i].Url,
myUrlsSection.Urls[i].Port);
}
}
Console.ReadLine();
}
}
}
' Set Assembly name to ConfigurationElement
' and set Root namespace to Samples.AspNet
Imports System.Configuration
Imports System.Collections
Class TestConfigurationElement
' Entry point for console application that reads the
' app.config file and writes to the console the
' URLs in the custom section.
Shared Sub Main(ByVal args() As String)
' Get the current configuration file.
Dim config As System.Configuration.Configuration = _
ConfigurationManager.OpenExeConfiguration( _
ConfigurationUserLevel.None)
' Get the MyUrls section.
Dim myUrlsSection As UrlsSection = _
config.GetSection("MyUrls")
If myUrlsSection Is Nothing Then
Console.WriteLine("Failed to load UrlsSection.")
Else
Console.WriteLine("The 'simple' element of app.config:")
Console.WriteLine(" Name={0} URL={1} Port={2}", _
myUrlsSection.Simple.Name, _
myUrlsSection.Simple.Url, _
myUrlsSection.Simple.Port)
Console.WriteLine("The urls collection of app.config:")
Dim i As Integer
For i = 0 To myUrlsSection.Urls.Count - 1
Console.WriteLine(" Name={0} URL={1} Port={2}", _
i, myUrlsSection.Urls(i).Name, _
myUrlsSection.Urls(i).Url, _
myUrlsSection.Urls(i).Port)
Next i
End If
Console.ReadLine()
End Sub
End Class
using System;
using System.Configuration;
using System.Collections;
namespace Samples.AspNet
{
// Define a custom section containing an individual
// element and a collection of elements.
public class UrlsSection : ConfigurationSection
{
[ConfigurationProperty("name",
DefaultValue = "MyFavorites",
IsRequired = true,
IsKey = false)]
[StringValidator(InvalidCharacters =
" ~!@#$%^&*()[]{}/;'\"|\\",
MinLength = 1, MaxLength = 60)]
public string Name
{
get
{
return (string)this["name"];
}
set
{
this["name"] = value;
}
}
// Declare an element (not in a collection) of the type
// UrlConfigElement. In the configuration
// file it corresponds to <simple .... />.
[ConfigurationProperty("simple")]
public UrlConfigElement Simple
{
get
{
UrlConfigElement url =
(UrlConfigElement)base["simple"];
return url;
}
}
// Declare a collection element represented
// in the configuration file by the sub-section
// <urls> <add .../> </urls>
// Note: the "IsDefaultCollection = false"
// instructs the .NET Framework to build a nested
// section like <urls> ...</urls>.
[ConfigurationProperty("urls",
IsDefaultCollection = false)]
public UrlsCollection Urls
{
get
{
UrlsCollection urlsCollection =
(UrlsCollection)base["urls"];
return urlsCollection;
}
}
protected override void DeserializeSection(
System.Xml.XmlReader reader)
{
base.DeserializeSection(reader);
// You can add custom processing code here.
}
protected override string SerializeSection(
ConfigurationElement parentElement,
string name, ConfigurationSaveMode saveMode)
{
string s =
base.SerializeSection(parentElement,
name, saveMode);
// You can add custom processing code here.
return s;
}
}
}
Imports System.Configuration
Imports System.Collections
' Define a custom section containing an individual
' element and a collection of elements.
Public Class UrlsSection
Inherits ConfigurationSection
<ConfigurationProperty("name", _
DefaultValue:="MyFavorites", _
IsRequired:=True, _
IsKey:=False), _
StringValidator( _
InvalidCharacters:=" ~!@#$%^&*()[]{}/;'""|\", _
MinLength:=1, MaxLength:=60)> _
Public Property Name() As String
Get
Return CStr(Me("name"))
End Get
Set(ByVal value As String)
Me("name") = value
End Set
End Property
' Declare an element (not in a collection) of the type
' UrlConfigElement. In the configuration
' file it corresponds to <simple .... />.
<ConfigurationProperty("simple")> _
Public ReadOnly Property Simple() _
As UrlConfigElement
Get
Dim url As UrlConfigElement = _
CType(Me("simple"), _
UrlConfigElement)
Return url
End Get
End Property
' Declare a collection element represented
' in the configuration file by the sub-section
' <urls> <add .../> </urls>
' Note: the "IsDefaultCollection = false"
' instructs the .NET Framework to build a nested
' section like <urls> ...</urls>.
<ConfigurationProperty("urls", _
IsDefaultCollection:=False)> _
Public ReadOnly Property Urls() _
As UrlsCollection
Get
Dim urlsCollection _
As UrlsCollection = _
CType(Me("urls"), UrlsCollection)
Return urlsCollection
End Get
End Property
Protected Overrides Sub DeserializeSection( _
ByVal reader As System.Xml.XmlReader)
MyBase.DeserializeSection(reader)
' Enter your custom processing code here.
End Sub
Protected Overrides Function SerializeSection( _
ByVal parentElement As ConfigurationElement, _
ByVal name As String, _
ByVal saveMode As ConfigurationSaveMode) As String
Dim s As String = _
MyBase.SerializeSection(parentElement, _
name, saveMode)
' Enter your custom processing code here.
Return s
End Function 'SerializeSection
End Class
using System;
using System.Configuration;
using System.Collections;
namespace Samples.AspNet
{
public class UrlsCollection : ConfigurationElementCollection
{
public UrlsCollection()
{
// Add one url to the collection. This is
// not necessary; could leave the collection
// empty until items are added to it outside
// the constructor.
UrlConfigElement url =
(UrlConfigElement)CreateNewElement();
Add(url);
}
public override
ConfigurationElementCollectionType CollectionType
{
get
{
return
ConfigurationElementCollectionType.AddRemoveClearMap;
}
}
protected override
ConfigurationElement CreateNewElement()
{
return new UrlConfigElement();
}
protected override
ConfigurationElement CreateNewElement(
string elementName)
{
return new UrlConfigElement(elementName);
}
protected override Object
GetElementKey(ConfigurationElement element)
{
return ((UrlConfigElement)element).Name;
}
public new string AddElementName
{
get
{ return base.AddElementName; }
set
{ base.AddElementName = value; }
}
public new string ClearElementName
{
get
{ return base.ClearElementName; }
set
{ base.ClearElementName = value; }
}
public new string RemoveElementName
{
get
{ return base.RemoveElementName; }
}
public new int Count
{
get { return base.Count; }
}
public UrlConfigElement this[int index]
{
get
{
return (UrlConfigElement)BaseGet(index);
}
set
{
if (BaseGet(index) != null)
{
BaseRemoveAt(index);
}
BaseAdd(index, value);
}
}
new public UrlConfigElement this[string Name]
{
get
{
return (UrlConfigElement)BaseGet(Name);
}
}
public int IndexOf(UrlConfigElement url)
{
return BaseIndexOf(url);
}
public void Add(UrlConfigElement url)
{
BaseAdd(url);
// Add custom code here.
}
protected override void
BaseAdd(ConfigurationElement element)
{
BaseAdd(element, false);
// Add custom code here.
}
public void Remove(UrlConfigElement url)
{
if (BaseIndexOf(url) >= 0)
BaseRemove(url.Name);
}
public void RemoveAt(int index)
{
BaseRemoveAt(index);
}
public void Remove(string name)
{
BaseRemove(name);
}
public void Clear()
{
BaseClear();
// Add custom code here.
}
}
}
Imports System.Configuration
Imports System.Collections
Public Class UrlsCollection
Inherits ConfigurationElementCollection
Public Sub New()
' Add one url to the collection. This is
' not necessary; could leave the collection
' empty until items are added to it outside
' the constructor.
Dim url As UrlConfigElement = _
CType(CreateNewElement(), UrlConfigElement)
' Add the element to the collection.
Add(url)
End Sub
Public Overrides ReadOnly Property CollectionType() _
As ConfigurationElementCollectionType
Get
Return ConfigurationElementCollectionType.AddRemoveClearMap
End Get
End Property
Protected Overloads Overrides Function CreateNewElement() _
As ConfigurationElement
Return New UrlConfigElement()
End Function 'CreateNewElement
Protected Overloads Overrides Function CreateNewElement( _
ByVal elementName As String) _
As ConfigurationElement
Return New UrlConfigElement(elementName)
End Function 'CreateNewElement
Protected Overrides Function GetElementKey( _
ByVal element As ConfigurationElement) As [Object]
Return CType(element, UrlConfigElement).Name
End Function 'GetElementKey
Public Shadows Property AddElementName() As String
Get
Return MyBase.AddElementName
End Get
Set(ByVal value As String)
MyBase.AddElementName = value
End Set
End Property
Public Shadows Property ClearElementName() As String
Get
Return MyBase.ClearElementName
End Get
Set(ByVal value As String)
MyBase.ClearElementName = value
End Set
End Property
Public Shadows ReadOnly Property RemoveElementName() As String
Get
Return MyBase.RemoveElementName
End Get
End Property
Public Shadows ReadOnly Property Count() As Integer
Get
Return MyBase.Count
End Get
End Property
Default Public Shadows Property Item( _
ByVal index As Integer) As UrlConfigElement
Get
Return CType(BaseGet(index), UrlConfigElement)
End Get
Set(ByVal value As UrlConfigElement)
If Not (BaseGet(index) Is Nothing) Then
BaseRemoveAt(index)
End If
BaseAdd(index, value)
End Set
End Property
Default Public Shadows ReadOnly Property Item( _
ByVal Name As String) As UrlConfigElement
Get
Return CType(BaseGet(Name), UrlConfigElement)
End Get
End Property
Public Function IndexOf( _
ByVal url As UrlConfigElement) As Integer
Return BaseIndexOf(url)
End Function 'IndexOf
Public Sub Add(ByVal url As UrlConfigElement)
BaseAdd(url)
' Add custom code here.
End Sub
Protected Overrides Sub BaseAdd( _
ByVal element As ConfigurationElement)
BaseAdd(element, False)
' Add custom code here.
End Sub
Public Overloads Sub Remove( _
ByVal url As UrlConfigElement)
If BaseIndexOf(url) >= 0 Then
BaseRemove(url.Name)
End If
End Sub
Public Sub RemoveAt(ByVal index As Integer)
BaseRemoveAt(index)
End Sub
Public Overloads Sub Remove(ByVal name As String)
BaseRemove(name)
End Sub
Public Sub Clear()
BaseClear()
End Sub
End Class
using System;
using System.Configuration;
using System.Collections;
namespace Samples.AspNet
{
public class UrlConfigElement : ConfigurationElement
{
// Constructor allowing name, url, and port to be specified.
public UrlConfigElement(String newName,
String newUrl, int newPort)
{
Name = newName;
Url = newUrl;
Port = newPort;
}
// Default constructor, will use default values as defined
// below.
public UrlConfigElement()
{
}
// Constructor allowing name to be specified, will take the
// default values for url and port.
public UrlConfigElement(string elementName)
{
Name = elementName;
}
[ConfigurationProperty("name",
DefaultValue = "Microsoft",
IsRequired = true,
IsKey = true)]
public string Name
{
get
{
return (string)this["name"];
}
set
{
this["name"] = value;
}
}
[ConfigurationProperty("url",
DefaultValue = "http://www.microsoft.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;
}
}
protected override void DeserializeElement(
System.Xml.XmlReader reader,
bool serializeCollectionKey)
{
base.DeserializeElement(reader,
serializeCollectionKey);
// You can your custom processing code here.
}
protected override bool SerializeElement(
System.Xml.XmlWriter writer,
bool serializeCollectionKey)
{
bool ret = base.SerializeElement(writer,
serializeCollectionKey);
// You can enter your custom processing code here.
return ret;
}
protected override bool IsModified()
{
bool ret = base.IsModified();
// You can enter your custom processing code here.
return ret;
}
}
}
Imports System.Configuration
Imports System.Collections
Public Class UrlConfigElement
Inherits ConfigurationElement
' Constructor allowing name, url, and port to be specified.
Public Sub New(ByVal newName As String, _
ByVal newUrl As String, _
ByVal newPort As Integer)
Name = newName
Url = newUrl
Port = newPort
End Sub
' Default constructor, will use default values as defined
Public Sub New()
End Sub
' Constructor allowing name to be specified, will take the
' default values for url and port.
Public Sub New(ByVal elementName As String)
Name = elementName
End Sub
<ConfigurationProperty("name", _
DefaultValue:="Microsoft", _
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.microsoft.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 Fix(Me("port"))
End Get
Set(ByVal value As Integer)
Me("port") = value
End Set
End Property
Protected Overrides Sub DeserializeElement(ByVal reader _
As System.Xml.XmlReader, _
ByVal serializeCollectionKey As Boolean)
MyBase.DeserializeElement(reader, _
serializeCollectionKey)
' Enter your custom processing code here.
End Sub
Protected Overrides Function SerializeElement(ByVal writer _
As System.Xml.XmlWriter, _
ByVal serializeCollectionKey As Boolean) As Boolean
Dim ret As Boolean = _
MyBase.SerializeElement(writer, serializeCollectionKey)
' Enter your custom processing code here.
Return ret
End Function 'SerializeElement
Protected Overrides Function IsModified() As Boolean
Dim ret As Boolean = MyBase.IsModified()
' Enter your custom processing code here.
Return ret
End Function 'IsModified
End Class
注解
ConfigurationElement是一个抽象类，用于表示配置文件 (（如 Web.config) ）中的 XML 元素。 配置文件中的元素可以包含零个、一个或多个子元素。
由于 类 ConfigurationElement 被定义为抽象类，因此无法创建它的实例。 只能从派生类。 .NET Framework包括派生自 ConfigurationElement 类的类，用于表示标准 XML 配置元素，例如 ConfigurationSection。 还可以扩展 类以 ConfigurationElement 访问自定义配置元素和节。 本主题后面包含的示例演示如何使用派生自 ConfigurationElement的自定义类访问自定义配置元素和部分。
还可以扩展标准配置类型，例如 ConfigurationElement、 ConfigurationElementCollection、 ConfigurationProperty和 ConfigurationSection。 有关详细信息，请参阅这些类的文档。
有关如何访问配置文件中的信息的详细信息，请参阅 ConfigurationManager 类和 WebConfigurationManager 类。
实施者说明
每个对象创建ConfigurationElement表示元素属性或子元素集合的 对象的内部ConfigurationPropertyCollectionConfigurationProperty集合。
不可自定义的信息和功能由 ElementInformation 属性提供的 ElementInformation 对象包含。
可以使用编程或声明性 (特性化) 编码模型创建自定义配置元素：
编程模型要求为每个元素属性创建一个属性来获取或设置其值，并将其添加到基础 ConfigurationElement 基类的内部属性包。 有关如何使用此模型的示例，请参阅 ConfigurationSection 类。
更简单的声明性模型（也称为特性化模型）允许您使用属性定义元素属性，然后使用属性对其进行修饰。 这些属性指示 ASP.NET 配置系统有关属性类型及其默认值的信息。 利用通过反射获取的此信息，ASP.NET 配置系统将为你创建元素属性对象并执行所需的初始化。 本主题后面所示的示例演示如何使用此模型。
构造函数
| ConfigurationElement() |
初始化 ConfigurationElement 类的新实例。 |
属性
| CurrentConfiguration |
获取对顶级 Configuration 实例的引用，该实例表示当前 ConfigurationElement 实例所属的配置层次结构。 |
| ElementInformation |
获取包含 ConfigurationElement 对象的不可自定义的信息和功能的 ElementInformation 对象。 |
| ElementProperty |
获取表示 ConfigurationElement 对象本身的 ConfigurationElementProperty 对象。 |
| EvaluationContext |
获取 ConfigurationElement 对象的 ContextInformation 对象。 |
| HasContext |
获取一个值，该值指示 CurrentConfiguration 属性是否为 |
| Item[ConfigurationProperty] |
获取或设置此配置元素的属性或特性。 |
| Item[String] |
获取或设置此配置元素的属性、特性或子元素。 |
| LockAllAttributesExcept |
获取被锁定的特性的集合。 |
| LockAllElementsExcept |
获取被锁定的元素的集合。 |
| LockAttributes |
获取被锁定的特性的集合。 |
| LockElements |
获取被锁定的元素的集合。 |
| LockItem |
获取或设置一个值，该值指示是否已锁定该元素。 |
| Properties |
获取属性的集合。 |
方法
适用于
另请参阅
反馈
即将发布：在整个 2024 年，我们将逐步淘汰作为内容反馈机制的“GitHub 问题”，并将其取代为新的反馈系统。 有关详细信息，请参阅：https://aka.ms/ContentUserFeedback。
提交和查看相关反馈