ConfigurationCollectionAttribute Clase

Definición

De forma declarativa, indica a .NET que cree una instancia de una colección de elementos de configuración. Esta clase no puede heredarse.

public ref class ConfigurationCollectionAttribute sealed : Attribute
[System.AttributeUsage(System.AttributeTargets.Class | System.AttributeTargets.Property)]
public sealed class ConfigurationCollectionAttribute : Attribute
[<System.AttributeUsage(System.AttributeTargets.Class | System.AttributeTargets.Property)>]
type ConfigurationCollectionAttribute = class
    inherit Attribute
Public NotInheritable Class ConfigurationCollectionAttribute
Inherits Attribute
Herencia
ConfigurationCollectionAttribute
Atributos

Ejemplos

En el ejemplo siguiente se muestra cómo usar .ConfigurationCollectionAttribute

Este ejemplo consta de tres clases: UrlsSection, UrlsCollectiony UrlConfigElement. La UrlsSection clase usa ConfigurationCollectionAttribute para definir una sección de configuración personalizada. Esta sección contiene una colección de direcciones URL (definida por la UrlsCollection clase ) de elementos url (definidos por la UrlConfigElement clase ). Al ejecutar el ejemplo, se crea una instancia de la UrlsSection clase y se generan los siguientes elementos de configuración en el archivo de configuración de la aplicación:

<configuration>  
    <configSections>  
        <section name="MyUrls" type="UrlsSection,   
          ConfigurationCollectionAttribute, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null" />  
    </configSections>  
    <MyUrls>  
        <urls>  
            <remove name="Contoso" />  
            <add name="Contoso" url="http://www.contoso.com" port="0" />  
        </urls>  
    </MyUrls>  
</configuration  

using System;
using System.Configuration;

// Define a custom section that contains a custom
// UrlsCollection collection of custom UrlConfigElement elements.
// This class shows how to use the ConfigurationCollectionAttribute.
public class UrlsSection : ConfigurationSection
{
    // Declare the Urls collection property using the
    // ConfigurationCollectionAttribute.
    // This allows to build a nested section that contains
    // a collection of elements.
    [ConfigurationProperty("urls", IsDefaultCollection = false)]
    [ConfigurationCollection(typeof(UrlsCollection),
        AddItemName = "add",
        ClearItemsName = "clear",
        RemoveItemName = "remove")]
    public UrlsCollection Urls
    {
        get
        {
            UrlsCollection urlsCollection =
                (UrlsCollection)base["urls"];
            return urlsCollection;
        }
    }
}

// Define the custom UrlsCollection that contains the 
// custom UrlsConfigElement elements.
public class UrlsCollection : ConfigurationElementCollection
{
    public UrlsCollection()
    {
        UrlConfigElement url = (UrlConfigElement)CreateNewElement();
        Add(url);
    }

    public override ConfigurationElementCollectionType CollectionType
    {
        get
        {
            return ConfigurationElementCollectionType.AddRemoveClearMap;
        }
    }

    protected override ConfigurationElement CreateNewElement()
    {
        return new UrlConfigElement();
    }

    protected override Object GetElementKey(ConfigurationElement element)
    {
        return ((UrlConfigElement)element).Name;
    }

    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);
    }
    protected override void BaseAdd(ConfigurationElement element)
    {
        BaseAdd(element, false);
    }

    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();
    }
}

// Define the custom UrlsConfigElement elements that are contained 
// by the custom UrlsCollection.
// Notice that you can change the default values to create new default elements.
public class UrlConfigElement : ConfigurationElement
{
    public UrlConfigElement(String name, String url)
    {
        this.Name = name;
        this.Url = url;
    }

    public UrlConfigElement()
    {

        this.Name = "Contoso";
        this.Url = "http://www.contoso.com";
        this.Port = 0;
    }

    [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 that contains a custom
' UrlsCollection collection of custom UrlConfigElement elements.
' This class shows how to use the ConfigurationCollectionAttribute.
Public Class UrlsSection
    Inherits ConfigurationSection
    ' Declare the Urls collection property using the
    ' ConfigurationCollectionAttribute.
    ' This allows to build a nested section that contains
    ' a collection of elements.
    <ConfigurationProperty("urls", IsDefaultCollection:=False),
        System.Configuration.ConfigurationCollection(GetType(UrlsCollection),
        AddItemName:="add", ClearItemsName:="clear", RemoveItemName:="remove")> _
    Public ReadOnly Property Urls() As UrlsCollection
        Get
            Dim urlsCollection As UrlsCollection = CType(MyBase.Item("urls"), UrlsCollection)
            Return urlsCollection
        End Get
    End Property

End Class

' Define the custom UrlsCollection that contains the 
' custom UrlsConfigElement elements.
Public Class UrlsCollection
    Inherits ConfigurationElementCollection
    Public Sub New()
        Dim url As UrlConfigElement = CType(CreateNewElement(), UrlConfigElement)
        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

    Protected Overrides Function GetElementKey(ByVal element As ConfigurationElement) As Object
        Return (CType(element, UrlConfigElement)).Name
    End Function

    Default Shadows Property Item(ByVal index As Integer) As UrlConfigElement
        Get
            Return CType(BaseGet(index), UrlConfigElement)
        End Get
        Set(ByVal value As UrlConfigElement)
            If BaseGet(index) IsNot 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

    Public Sub Add(ByVal url As UrlConfigElement)
        BaseAdd(url)
    End Sub
    Protected Overloads Overrides Sub BaseAdd(ByVal element As ConfigurationElement)
        BaseAdd(element, False)
    End Sub

    Public 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 Sub Remove(ByVal name As String)
        BaseRemove(name)
    End Sub

    Public Sub Clear()
        BaseClear()
    End Sub
End Class

' Define the custom UrlsConfigElement elements that are contained 
' by the custom UrlsCollection.
Public Class UrlConfigElement
    Inherits ConfigurationElement
    Public Sub New(ByVal name As String, ByVal url As String)
        Me.Name = name
        Me.Url = url
    End Sub

    Public Sub New()
        Me.Name = "Contoso"
        Me.Url = "http://www.contoso.com"
        Me.Port = 0
    End Sub

    <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;

class UsingConfigurationCollectionAttribute
{

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

            // Create a custom configuration section.
            UrlsSection myUrlsSection = 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["MyUrls"] == null)
            {
                config.Sections.Add("MyUrls", myUrlsSection);
            }

            // Save the application configuration file.
            myUrlsSection.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 myUrlsSection =
               ConfigurationManager.GetSection("MyUrls") as UrlsSection;

            if (myUrlsSection == null)
            {
                Console.WriteLine("Failed to load UrlsSection.");
            }
            else
            {
                Console.WriteLine("URLs defined in the configuration file:");
                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);
                }
            }
        }
        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();
        Console.WriteLine("Enter any key to exit.");

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


Friend Class UsingConfigurationCollectionAttribute

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

            ' Create a custom configuration section.
            Dim myUrlsSection 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("MyUrls") Is Nothing Then
                config.Sections.Add("MyUrls", myUrlsSection)
            End If


            ' Save the application configuration file.
            myUrlsSection.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 myUrlsSection As UrlsSection = TryCast(ConfigurationManager.GetSection("MyUrls"), UrlsSection)

            If myUrlsSection Is Nothing Then
                Console.WriteLine("Failed to load UrlsSection.")
            Else
                Console.WriteLine("URLs defined in app.config:")
                For i As Integer = 0 To myUrlsSection.Urls.Count - 1
                    Console.WriteLine("  Name={0} URL={1} Port={2}", myUrlsSection.Urls(i).Name, myUrlsSection.Urls(i).Url, myUrlsSection.Urls(i).Port)
                Next i
            End If
        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()
        Console.WriteLine("Enter any key to exit.")

        Console.ReadLine()
    End Sub
End Class

Comentarios

El atributo se usa ConfigurationCollectionAttribute para decorar un ConfigurationElementCollection elemento. Esto indica a .NET que cree una instancia de la colección y que la inicialice con los valores personalizados ConfigurationElement .

Nota

La manera más sencilla de crear un elemento de configuración personalizado es usar el modelo con atributos (declarativos). Los elementos se declaran y se decoran con el ConfigurationCollectionAttribute atributo . Para cada elemento marcado con este atributo, .NET usa la reflexión para leer los parámetros de decoración y crear una instancia relacionada ConfigurationElementCollection . También puede usar el modelo de programación. En este caso, es su responsabilidad declarar la colección pública personalizada, pero también invalidar el ConfigurationElementCollection miembro y devolver la colección de propiedades.

El sistema de configuración de .NET proporciona tipos de atributo que puede usar durante la creación de elementos de configuración personalizados. Hay dos tipos de atributos:

Constructores

ConfigurationCollectionAttribute(Type)

Inicializa una nueva instancia de la clase ConfigurationCollectionAttribute.

Propiedades

AddItemName

Obtiene o establece el nombre del elemento de configuración <add>.

ClearItemsName

Obtiene o establece el nombre del elemento de configuración <clear>.

CollectionType

Obtiene o establece el tipo del atributo ConfigurationCollectionAttribute.

ItemType

Obtiene el tipo del elemento de colección.

RemoveItemName

Obtiene o establece el nombre del elemento de configuración <remove>.

TypeId

Cuando se implementa en una clase derivada, obtiene un identificador único para este Attribute.

(Heredado de Attribute)

Métodos

Equals(Object)

Devuelve un valor que indica si esta instancia es igual que un objeto especificado.

(Heredado de Attribute)
GetHashCode()

Devuelve el código hash de esta instancia.

(Heredado de Attribute)
GetType()

Obtiene el Type de la instancia actual.

(Heredado de Object)
IsDefaultAttribute()

Si se reemplaza en una clase derivada, indica si el valor de esta instancia es el valor predeterminado de la clase derivada.

(Heredado de Attribute)
Match(Object)

Cuando se invalida en una clase derivada, devuelve un valor que indica si esta instancia es igual a un objeto especificado.

(Heredado de Attribute)
MemberwiseClone()

Crea una copia superficial del Object actual.

(Heredado de Object)
ToString()

Devuelve una cadena que representa el objeto actual.

(Heredado de Object)

Implementaciones de interfaz explícitas

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

Asigna un conjunto de nombres a un conjunto correspondiente de identificadores de envío.

(Heredado de Attribute)
_Attribute.GetTypeInfo(UInt32, UInt32, IntPtr)

Obtiene la información de tipos de un objeto, que puede utilizarse para obtener la información de tipos de una interfaz.

(Heredado de Attribute)
_Attribute.GetTypeInfoCount(UInt32)

Recupera el número de interfaces de información de tipo que proporciona un objeto (0 ó 1).

(Heredado de Attribute)
_Attribute.Invoke(UInt32, Guid, UInt32, Int16, IntPtr, IntPtr, IntPtr, IntPtr)

Proporciona acceso a las propiedades y los métodos expuestos por un objeto.

(Heredado de Attribute)

Se aplica a

Consulte también