ConfigurationElementCollection クラス

定義

public ref class ConfigurationElementCollection abstract : System::Configuration::ConfigurationElement, System::Collections::ICollection

public abstract class ConfigurationElementCollection : System.Configuration.ConfigurationElement, System.Collections.ICollection

type ConfigurationElementCollection = class
    inherit ConfigurationElement
    interface ICollection
    interface IEnumerable

Public MustInherit Class ConfigurationElementCollection
Inherits ConfigurationElement
Implements ICollection

継承

Object

ConfigurationElement

ConfigurationElementCollection

派生

System.Configuration.ConnectionStringSettingsCollection

System.Configuration.KeyValueConfigurationCollection

System.Configuration.NameValueConfigurationCollection

System.Configuration.ProviderSettingsCollection

System.Configuration.SchemeSettingElementCollection

その他…

実装

ICollection IEnumerable

例

次の例は、 を使用する方法を ConfigurationElementCollection示しています。

最初の例は、 の 3 つのクラス UrlsSectionUrlsCollectionUrlConfigElementで構成されています。 クラスは UrlsSection 、 を ConfigurationCollectionAttribute 使用してカスタム構成セクションを定義します。 このセクションには、(クラスによって定義される UrlsCollection ) URL 要素の URL コレクション (クラスによって定義されます) が UrlConfigElement 含まれています。

using System;
using System.Configuration;

// Define a UrlsSection custom section that contains a 
// UrlsCollection collection of UrlConfigElement elements.
public class UrlsSection : ConfigurationSection
{

    // Declare the UrlsCollection collection property.
    [ConfigurationProperty("urls", IsDefaultCollection = false)]
    [ConfigurationCollection(typeof(UrlsCollection),
        AddItemName = "add",
        ClearItemsName = "clear",
        RemoveItemName = "remove")]
    public UrlsCollection Urls
    {
        get
        {
            UrlsCollection urlsCollection =
                (UrlsCollection)base["urls"];

            return urlsCollection;
        }

        set
        {
            UrlsCollection urlsCollection = value;
        }
    }

    // Create a new instance of the UrlsSection.
    // This constructor creates a configuration element 
    // using the UrlConfigElement default values.
    // It assigns this element to the collection.
    public UrlsSection()
    {
        UrlConfigElement url = new UrlConfigElement();
        Urls.Add(url);
    }
}

// Define the UrlsCollection that contains the 
// UrlsConfigElement elements.
// This class shows how to use the ConfigurationElementCollection.
public class UrlsCollection : ConfigurationElementCollection
{

    public UrlsCollection()
    {
    }

    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);

        // Your custom code goes here.
    }

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

        // Your custom code goes here.
    }
    
    public void Remove(UrlConfigElement url)
    {
        if (BaseIndexOf(url) >= 0)
        {
            BaseRemove(url.Name);
            // Your custom code goes here.
            Console.WriteLine("UrlsCollection: {0}", "Removed collection element!");
        }
    }
    
    public void RemoveAt(int index)
    {
        BaseRemoveAt(index);

        // Your custom code goes here.
    }
    
    public void Remove(string name)
    {
        BaseRemove(name);

        // Your custom code goes here.
    }
    
    public void Clear()
    {
        BaseClear();

        // Your custom code goes here.
        Console.WriteLine("UrlsCollection: {0}", "Removed entire collection!");
    }
}

// Define the UrlsConfigElement elements that are contained 
// by the UrlsCollection.
public class UrlConfigElement : ConfigurationElement
{
    public UrlConfigElement(String name, String url, int port)
    {
        this.Name = name;
        this.Url = url;
        this.Port = port;
    }

    public UrlConfigElement()
    {
    }

    [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)4040, 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 UrlsSection custom section that contains a 
' UrlsCollection collection of UrlConfigElement elements.
Public Class UrlsSection
    Inherits ConfigurationSection

    ' Declare the UrlsCollection collection property.
    <ConfigurationProperty("urls", IsDefaultCollection:=False), ConfigurationCollection(GetType(UrlsCollection), AddItemName:="add", ClearItemsName:="clear", RemoveItemName:="remove")>
    Public Property Urls() As UrlsCollection
        Get
            Dim urlsCollection As UrlsCollection = CType(MyBase.Item("urls"), UrlsCollection)

            Return urlsCollection
        End Get

        Set(ByVal value As UrlsCollection)
            Dim urlsCollection As UrlsCollection = value
        End Set

    End Property

    ' Create a new instance of the UrlsSection.
    ' This constructor creates a configuration element 
    ' using the UrlConfigElement default values.
    ' It assigns this element to the collection.
    Public Sub New()
        Dim url As New UrlConfigElement()
        Urls.Add(url)

    End Sub

End Class

' Define the UrlsCollection that contains the 
' UrlsConfigElement elements.
' This class shows how to use the ConfigurationElementCollection.
Public Class UrlsCollection
    Inherits System.Configuration.ConfigurationElementCollection


    Public Sub New()

    End Sub

    Public 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 Public 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(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)

        ' Your custom code goes here.

    End Sub

    Protected Overloads Sub BaseAdd(ByVal element As ConfigurationElement)
        BaseAdd(element, False)

        ' Your custom code goes here.

    End Sub

    Public Sub Remove(ByVal url As UrlConfigElement)
        If BaseIndexOf(url) >= 0 Then
            BaseRemove(url.Name)
            ' Your custom code goes here.
            Console.WriteLine("UrlsCollection: {0}", "Removed collection element!")
        End If
    End Sub

    Public Sub RemoveAt(ByVal index As Integer)
        BaseRemoveAt(index)

        ' Your custom code goes here.

    End Sub

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

        ' Your custom code goes here.

    End Sub

    Public Sub Clear()
        BaseClear()

        ' Your custom code goes here.
        Console.WriteLine("UrlsCollection: {0}", "Removed entire collection!")
    End Sub

End Class

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

    Public Sub New()

    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:=CInt(4040), 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

この 2 番目のコード例では、前に指定したクラスを使用します。 コンソール アプリケーション プロジェクトでは、これら 2 つの例を組み合わせます。

using System;
using System.Configuration;
using System.Text;

class UsingConfigurationCollectionElement
{

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

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

            // Add the custom section to the application
            // configuration file.
            UrlsSection myUrlsSection = (UrlsSection)config.Sections["MyUrls"];

            if (myUrlsSection == null)
            {
                //  The configuration file does not contain the
                // custom section yet. Create it.
                myUrlsSection = new UrlsSection();

                config.Sections.Add("MyUrls", myUrlsSection);

                // Save the application configuration file.
                myUrlsSection.SectionInformation.ForceSave = true;
                config.Save(ConfigurationSaveMode.Modified); 
            }
            else
                if (myUrlsSection.Urls.Count == 0)
                {

                    // The configuration file contains the
                    // custom section but its element collection is empty.
                    // Initialize the collection. 
                    UrlConfigElement url = new UrlConfigElement();
                    myUrlsSection.Urls.Add(url);

                    // 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 =
               config.GetSection("MyUrls") as UrlsSection;

            if (myUrlsSection == null)
            {
                Console.WriteLine("Failed to load UrlsSection.");
            }
            else
            {
                Console.WriteLine("Collection elements contained in the custom section collection:");
                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());
        }
    }

    // Add an element to the custom section collection.
    // This function uses the ConfigurationCollectionElement Add method.
    static void AddCollectionElement()
    {
        try
        {

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

            // Get the custom configuration section.
            UrlsSection myUrlsSection = config.GetSection("MyUrls") as UrlsSection;

            // Add the element to the collection in the custom section.
            if (config.Sections["MyUrls"] != null)
            {
                UrlConfigElement urlElement = new UrlConfigElement();
                urlElement.Name = "Microsoft";
                urlElement.Url = "http://www.microsoft.com";
                urlElement.Port = 8080;
                
                // Use the ConfigurationCollectionElement Add method
                // to add the new element to the collection.
                myUrlsSection.Urls.Add(urlElement);

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

                Console.WriteLine("Added collection element to the custom section in the configuration file: {0}",
                    config.FilePath);
                Console.WriteLine();
            }
            else
            {
                Console.WriteLine("You must create the custom section first.");
            }
        }
        catch (ConfigurationErrorsException err)
        {
            Console.WriteLine("AddCollectionElement: {0}", err.ToString());
        }
    }

    // Remove element from the custom section collection.
    // This function uses one of the ConfigurationCollectionElement 
    // overloaded Remove methods.
    static void RemoveCollectionElement()
    {
        try
        {

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

            // Get the custom configuration section.
            UrlsSection myUrlsSection = config.GetSection("MyUrls") as UrlsSection;

            // Remove the element from the custom section.
            if (config.Sections["MyUrls"] != null)
            {
                UrlConfigElement urlElement = new UrlConfigElement();
                urlElement.Name = "Microsoft";
                urlElement.Url = "http://www.microsoft.com";
                urlElement.Port = 8080;

                // Use one of the ConfigurationCollectionElement Remove 
                // overloaded methods to remove the element from the collection.
                myUrlsSection.Urls.Remove(urlElement);

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

                Console.WriteLine("Removed collection element from he custom section in the configuration file: {0}",
                    config.FilePath);
                Console.WriteLine();
            }
            else
            {
                Console.WriteLine("You must create the custom section first.");
            }
        }
        catch (ConfigurationErrorsException err)
        {
            Console.WriteLine("RemoveCollectionElement: {0}", err.ToString());
        }
    }

    // Remove the collection of elements from the custom section.
    // This function uses the ConfigurationCollectionElement Clear method.
    static void ClearCollectionElements()
    {
        try
        {

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

            // Get the custom configuration section.
            UrlsSection myUrlsSection = config.GetSection("MyUrls") as UrlsSection;

            // Remove the collection of elements from the section.
            if (config.Sections["MyUrls"] != null)
            {
                myUrlsSection.Urls.Clear();

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

                Console.WriteLine("Removed collection of elements from he custom section in the configuration file: {0}",
                    config.FilePath);
                Console.WriteLine();
            }
            else
            {
                Console.WriteLine("You must create the custom section first.");
            }
        }
        catch (ConfigurationErrorsException err)
        {
            Console.WriteLine("ClearCollectionElements: {0}", err.ToString());
        }
    }

    public static void UserMenu()
    {
        string applicationName =
           Environment.GetCommandLineArgs()[0] + ".exe";
        StringBuilder buffer = new StringBuilder();

        buffer.AppendLine("Application: " + applicationName);
        buffer.AppendLine("Make your selection.");
        buffer.AppendLine("?    -- Display help.");
        buffer.AppendLine("Q,q  -- Exit the application.");
        buffer.Append("1    -- Create a custom section that");
        buffer.AppendLine(" contains a collection of elements.");
        buffer.Append("2    -- Read the custom section that");
        buffer.AppendLine(" contains a collection of custom elements.");
        buffer.Append("3    -- Add a collection element to");
        buffer.AppendLine(" the custom section.");
        buffer.Append("4    -- Remove a collection element from");
        buffer.AppendLine(" the custom section.");
        buffer.Append("5    -- Clear the collection of elements from");
        buffer.AppendLine(" the custom section.");
        
        Console.Write(buffer.ToString());
    }

    // Obtain user's input and provide
    // feedback.
    static void Main(string[] args)
    {
        // Define user selection string.
        string selection;

        // Get the name of the application.
        string appName =
          Environment.GetCommandLineArgs()[0];

        // Get user selection.
        while (true)
        {

            UserMenu();
            Console.Write("> ");
            selection = Console.ReadLine();
            if (!string.IsNullOrEmpty(selection))
                break;
        }

        while (selection.ToLower() != "q")
        {
            // Process user's input.
            switch (selection)
            {
                case "1":
                    // Create a custom section and save it in the 
                    // application configuration file.
                    CreateCustomSection();
                    break;

                case "2":
                    // Read the custom section from the
                    // application configuration file.
                    ReadCustomSection();
                    break;

                case "3":
                    // Add a collection element to the
                    // custom section.
                    AddCollectionElement();
                    break;

                case "4":
                    // Remove a collection element from the
                    // custom section.
                    RemoveCollectionElement();
                    break;

                case "5":
                    // Clear the collection of elements from the
                    // custom section.
                    ClearCollectionElements();
                    break;

                default:
                    UserMenu();
                    break;
            }
            Console.Write("> ");
            selection = Console.ReadLine();
        }
    }
}

Imports System.Configuration
Imports System.Text

Friend Class UsingConfigurationCollectionElement

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

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

            ' Add the custom section to the application
            ' configuration file.
            Dim myUrlsSection As UrlsSection = CType(config.Sections("MyUrls"), UrlsSection)

            If myUrlsSection Is Nothing Then
                '  The configuration file does not contain the
                ' custom section yet. Create it.
                myUrlsSection = New UrlsSection()

                config.Sections.Add("MyUrls", myUrlsSection)

                ' Save the application configuration file.
                myUrlsSection.SectionInformation.ForceSave = True
                config.Save(ConfigurationSaveMode.Modified)
            Else
                If myUrlsSection.Urls.Count = 0 Then

                    ' The configuration file contains the
                    ' custom section but its element collection is empty.
                    ' Initialize the collection. 
                    Dim url As New UrlConfigElement()
                    myUrlsSection.Urls.Add(url)

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


            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(config.GetSection("MyUrls"), UrlsSection)

            If myUrlsSection Is Nothing Then
                Console.WriteLine("Failed to load UrlsSection.")
            Else
                Console.WriteLine("Collection elements contained in the custom section collection:")
                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

    ' Add an element to the custom section collection.
    ' This function uses the ConfigurationCollectionElement Add method.
    Private Shared Sub AddCollectionElement()
        Try

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


            ' Get the custom configuration section.
            Dim myUrlsSection As UrlsSection = TryCast(config.GetSection("MyUrls"), UrlsSection)


            ' Add the element to the collection in the custom section.
            If config.Sections("MyUrls") IsNot Nothing Then
                Dim urlElement As New UrlConfigElement()
                urlElement.Name = "Microsoft"
                urlElement.Url = "http://www.microsoft.com"
                urlElement.Port = 8080

                ' Use the ConfigurationCollectionElement Add method
                ' to add the new element to the collection.
                myUrlsSection.Urls.Add(urlElement)


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


                Console.WriteLine("Added collection element to the custom section in the configuration file: {0}", config.FilePath)
                Console.WriteLine()
            Else
                Console.WriteLine("You must create the custom section first.")
            End If

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

    End Sub

    ' Remove element from the custom section collection.
    ' This function uses one of the ConfigurationCollectionElement 
    ' overloaded Remove methods.
    Private Shared Sub RemoveCollectionElement()
        Try

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


            ' Get the custom configuration section.
            Dim myUrlsSection As UrlsSection = TryCast(config.GetSection("MyUrls"), UrlsSection)


            ' Remove the element from the custom section.
            If config.Sections("MyUrls") IsNot Nothing Then
                Dim urlElement As New UrlConfigElement()
                urlElement.Name = "Microsoft"
                urlElement.Url = "http://www.microsoft.com"
                urlElement.Port = 8080

                ' Use one of the ConfigurationCollectionElement Remove 
                ' overloaded methods to remove the element from the collection.
                myUrlsSection.Urls.Remove(urlElement)


                ' Save the application configuration file.
                myUrlsSection.SectionInformation.ForceSave = True
                config.Save(ConfigurationSaveMode.Full)


                Console.WriteLine("Removed collection element from he custom section in the configuration file: {0}", config.FilePath)
                Console.WriteLine()
            Else
                Console.WriteLine("You must create the custom section first.")
            End If

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

    End Sub

    ' Remove the collection of elements from the custom section.
    ' This function uses the ConfigurationCollectionElement Clear method.
    Private Shared Sub ClearCollectionElements()
        Try

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


            ' Get the custom configuration section.
            Dim myUrlsSection As UrlsSection = TryCast(config.GetSection("MyUrls"), UrlsSection)


            ' Remove the collection of elements from the section.
            If config.Sections("MyUrls") IsNot Nothing Then
                myUrlsSection.Urls.Clear()


                ' Save the application configuration file.
                myUrlsSection.SectionInformation.ForceSave = True
                config.Save(ConfigurationSaveMode.Full)


                Console.WriteLine("Removed collection of elements from he custom section in the configuration file: {0}", config.FilePath)
                Console.WriteLine()
            Else
                Console.WriteLine("You must create the custom section first.")
            End If

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

    End Sub

    Public Shared Sub UserMenu()
        Dim applicationName As String = Environment.GetCommandLineArgs()(0) & ".exe"
        Dim buffer As New StringBuilder()

        buffer.AppendLine("Application: " & applicationName)
        buffer.AppendLine("Make your selection.")
        buffer.AppendLine("?    -- Display help.")
        buffer.AppendLine("Q,q  -- Exit the application.")
        buffer.Append("1    -- Create a custom section that")
        buffer.AppendLine(" contains a collection of elements.")
        buffer.Append("2    -- Read the custom section that")
        buffer.AppendLine(" contains a collection of custom elements.")
        buffer.Append("3    -- Add a collection element to")
        buffer.AppendLine(" the custom section.")
        buffer.Append("4    -- Remove a collection element from")
        buffer.AppendLine(" the custom section.")
        buffer.Append("5    -- Clear the collection of elements from")
        buffer.AppendLine(" the custom section.")

        Console.Write(buffer.ToString())
    End Sub

    ' Obtain user's input and provide
    ' feedback.
    Shared Sub Main(ByVal args() As String)
        ' Define user selection string.
        Dim selection As String

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

        ' Get user selection.
        Do

            UserMenu()
            Console.Write("> ")
            selection = Console.ReadLine()
            If selection <> String.Empty Then
                Exit Do
            End If
        Loop

        Do While selection.ToLower() <> "q"
            ' Process user's input.
            Select Case selection
                Case "1"
                    ' Create a custom section and save it in the 
                    ' application configuration file.
                    CreateCustomSection()

                Case "2"
                    ' Read the custom section from the
                    ' application configuration file.
                    ReadCustomSection()

                Case "3"
                    ' Add a collection element to the
                    ' custom section.
                    AddCollectionElement()

                Case "4"
                    ' Remove a collection element from the
                    ' custom section.
                    RemoveCollectionElement()

                Case "5"
                    ' Clear the collection of elements from the
                    ' custom section.
                    ClearCollectionElements()

                Case Else
                    UserMenu()
            End Select
            Console.Write("> ")
            selection = Console.ReadLine()
        Loop
    End Sub
End Class

コンソール アプリケーションを実行すると、 クラスの UrlsSection インスタンスが作成され、アプリケーション構成ファイルに次の構成要素が生成されます。

<configuration>  
    <configSections>  
        <section name="MyUrls" type="UrlsSection,   
          ConfigurationElementCollection, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null" />  
    </configSections>  
    <MyUrls>  
        <urls>  
           <add name="Contoso" url="http://www.contoso.com" port="4040" />  
        </urls>  
    </MyUrls>  
</configuration  

注釈

は ConfigurationElementCollection 、構成ファイル内の要素のコレクションを表します。

オブジェクトのConfigurationElementCollectionConfigurationElementコレクションを操作するには、 を使用します。 カスタム ConfigurationElement 要素のコレクションを に追加するには、このクラスを ConfigurationSection実装します。

注意 (実装者)

プログラムまたは宣言型 (属性付き) コーディング モデルを使用して、カスタム構成要素を作成できます。

プログラム モデルでは、要素属性ごとにプロパティを作成してその値を取得および設定し、基になる ConfigurationElement 基底クラスの内部プロパティ バッグに追加する必要があります。

宣言型モデル (属性付きモデルとも呼ばれます) を使用すると、プロパティを使用して属性を構成することで、要素属性を定義できます。 これらの属性は、プロパティの種類とその既定値について ASP.NET 構成システムに指示します。 ASP.NET リフレクションを使用してこの情報を取得し、要素プロパティ オブジェクトを作成し、必要な初期化を実行できます。

コンストラクター

プロパティ

メソッド

明示的なインターフェイスの実装

拡張メソッド

適用対象

こちらもご覧ください

• ElementInformation
• ConfigurationElement
• ConfigurationElementCollectionType
• ConfigurationProperty
• ConfigurationPropertyCollection
• ConfigurationSection