テキスト サイト マップ プロバイダの例
更新 : 2007 年 11 月
完全なテキストベースのサイト マップ プロバイダを示します。
例
説明
SiteMapProvider 抽象クラスを実装するクラスを記述する方法を次のコード例に示します。
コード
Imports System
Imports System.Collections
Imports System.Collections.Specialized
Imports System.Configuration.Provider
Imports System.IO
Imports System.Security.Permissions
Imports System.Web
Namespace Samples.AspNet.VB
<AspNetHostingPermission(SecurityAction.Demand, Level:=AspNetHostingPermissionLevel.Minimal)> _
Public Class SimpleTextSiteMapProvider
Inherits SiteMapProvider
Private parentSiteMapProvider As SiteMapProvider = Nothing
Private simpleTextProviderName As String = Nothing
Private sourceFilename As String = Nothing
Private aRootNode As SiteMapNode = Nothing
Private siteMapNodes As ArrayList = Nothing
Private childParentRelationship As ArrayList = Nothing
' A default constructor. The Name property is initialized in the
' Initialize method.
Public Sub New()
End Sub 'New
' Implement the CurrentNode property.
Public Overrides ReadOnly Property CurrentNode() As SiteMapNode
Get
Dim currentUrl As String = FindCurrentUrl()
' Find the SiteMapNode that represents the current page.
Dim aCurrentNode As SiteMapNode = FindSiteMapNode(currentUrl)
Return aCurrentNode
End Get
End Property
' Implement the RootNode property.
Public Overrides ReadOnly Property RootNode() As SiteMapNode
Get
Return aRootNode
End Get
End Property
' Implement the ParentProvider property.
Public Overrides Property ParentProvider() As SiteMapProvider
Get
Return parentSiteMapProvider
End Get
Set(ByVal value As SiteMapProvider)
parentSiteMapProvider = Value
End Set
End Property
' Implement the RootProvider property.
Public Overrides ReadOnly Property RootProvider() As SiteMapProvider
Get
' If the current instance belongs to a provider hierarchy, it
' cannot be the RootProvider. Rely on the ParentProvider.
If Not (Me.ParentProvider Is Nothing) Then
Return ParentProvider.RootProvider
' If the current instance does not have a ParentProvider, it is
' not a child in a hierarchy, and can be the RootProvider.
Else
Return Me
End If
End Get
End Property
' Implement the FindSiteMapNode method.
Public Overrides Function FindSiteMapNode(ByVal rawUrl As String) As SiteMapNode
' Does the root node match the URL?
If RootNode.Url = rawUrl Then
Return RootNode
Else
Dim candidate As SiteMapNode = Nothing
' Retrieve the SiteMapNode that matches the URL.
SyncLock Me
candidate = GetNode(siteMapNodes, rawUrl)
End SyncLock
Return candidate
End If
End Function 'FindSiteMapNode
' Implement the GetChildNodes method.
Public Overrides Function GetChildNodes(ByVal node As SiteMapNode) As SiteMapNodeCollection
Dim children As New SiteMapNodeCollection()
' Iterate through the ArrayList and find all nodes that have the specified node as a parent.
SyncLock Me
Dim i As Integer
For i = 0 To childParentRelationship.Count - 1
Dim de As DictionaryEntry = CType(childParentRelationship(i), DictionaryEntry)
Dim nodeUrl As String = CType(de.Key, String)
Dim parent As SiteMapNode = GetNode(childParentRelationship, nodeUrl)
If Not (parent Is Nothing) AndAlso node.Url = parent.Url Then
' The SiteMapNode with the Url that corresponds to nodeUrl
' is a child of the specified node. Get the SiteMapNode for
' the nodeUrl.
Dim child As SiteMapNode = FindSiteMapNode(nodeUrl)
If Not (child Is Nothing) Then
children.Add(CType(child, SiteMapNode))
Else
Throw New Exception("ArrayLists not in sync.")
End If
End If
Next i
End SyncLock
Return children
End Function 'GetChildNodes
Protected Overrides Function GetRootNodeCore() As SiteMapNode
Return RootNode
End Function ' GetRootNodeCore()
' Implement the GetParentNode method.
Public Overrides Function GetParentNode(ByVal node As SiteMapNode) As SiteMapNode
' Check the childParentRelationship table and find the parent of the current node.
' If there is no parent, the current node is the RootNode.
Dim parent As SiteMapNode = Nothing
SyncLock Me
' Get the Value of the node in childParentRelationship
parent = GetNode(childParentRelationship, node.Url)
End SyncLock
Return parent
End Function 'GetParentNode
' Implement the ProviderBase.Initialize method.
' Initialize is used to initialize the state that the Provider holds, but
' not actually build the site map.
Public Overrides Sub Initialize(ByVal name As String, ByVal attributes As NameValueCollection)
SyncLock Me
MyBase.Initialize(name, attributes)
simpleTextProviderName = name
sourceFilename = attributes("siteMapFile")
siteMapNodes = New ArrayList()
childParentRelationship = New ArrayList()
' Build the site map in memory.
LoadSiteMapFromStore()
End SyncLock
End Sub 'Initialize
' Private helper methods
Private Function GetNode(ByVal list As ArrayList, ByVal url As String) As SiteMapNode
Dim i As Integer
For i = 0 To list.Count - 1
Dim item As DictionaryEntry = CType(list(i), DictionaryEntry)
If CStr(item.Key) = url Then
Return CType(item.Value, SiteMapNode)
End If
Next i
Return Nothing
End Function 'GetNode
' Get the URL of the currently displayed page.
Private Function FindCurrentUrl() As String
Try
' The current HttpContext.
Dim currentContext As HttpContext = HttpContext.Current
If Not (currentContext Is Nothing) Then
Return currentContext.Request.RawUrl
Else
Throw New Exception("HttpContext.Current is Invalid")
End If
Catch e As Exception
Throw New NotSupportedException("This provider requires a valid context.", e)
End Try
End Function 'FindCurrentUrl
Protected Overridable Sub LoadSiteMapFromStore()
Dim pathToOpen As String
SyncLock Me
' If a root node exists, LoadSiteMapFromStore has already
' been called, and the method can return.
If Not (aRootNode Is Nothing) Then
Return
Else
pathToOpen = HttpContext.Current.Server.MapPath("~" & "\\" & sourceFilename)
If File.Exists(pathToOpen) Then
' Open the file to read from.
Dim sr As StreamReader = File.OpenText(pathToOpen)
Try
' Clear the state of the collections and aRootNode
aRootNode = Nothing
siteMapNodes.Clear()
childParentRelationship.Clear()
' Parse the file and build the site map
Dim s As String = ""
Dim nodeValues As String() = Nothing
Dim temp As SiteMapNode = Nothing
Do
s = sr.ReadLine()
If Not s Is Nothing Then
' Build the various SiteMapNode objects and add
' them to the ArrayList collections. The format used
' is: URL,TITLE,DESCRIPTION,PARENTURL
nodeValues = s.Split(","c)
temp = New SiteMapNode(Me, _
HttpRuntime.AppDomainAppVirtualPath & "/" & nodeValues(0), _
HttpRuntime.AppDomainAppVirtualPath & "/" & nodeValues(0), _
nodeValues(1), _
nodeValues(2))
' Is this a root node yet?
If aRootNode Is Nothing AndAlso _
(nodeValues(3) Is Nothing OrElse _
nodeValues(3) = String.Empty) Then
aRootNode = temp
' If not the root node, add the node to the various collections.
Else
siteMapNodes.Add(New DictionaryEntry(temp.Url, temp))
' The parent node has already been added to the collection.
Dim parentNode As SiteMapNode = _
FindSiteMapNode(HttpRuntime.AppDomainAppVirtualPath & "/" & nodeValues(3))
If Not (parentNode Is Nothing) Then
childParentRelationship.Add(New DictionaryEntry(temp.Url, parentNode))
Else
Throw New Exception("Parent node not found for current node.")
End If
End If
End If
Loop Until s Is Nothing
Finally
sr.Close()
End Try
Else
Throw New Exception("File not found")
End If
End If
End SyncLock
Return
End Sub 'LoadSiteMapFromStore
End Class 'SimpleTextSiteMapProvider
End Namespace
using System;
using System.Configuration.Provider;
using System.Collections;
using System.Collections.Specialized;
using System.IO;
using System.Security.Permissions;
using System.Web;
namespace Samples.AspNet.CS
{
[AspNetHostingPermission(SecurityAction.Demand, Level = AspNetHostingPermissionLevel.Minimal)]
public class SimpleTextSiteMapProvider : SiteMapProvider
{
private SiteMapProvider parentSiteMapProvider = null;
private string simpleTextProviderName = null;
private string sourceFilename = null;
private SiteMapNode rootNode = null;
private ArrayList siteMapNodes = null;
private ArrayList childParentRelationship = null;
// A default constructor. The Name property is initialized in the
// Initialize method.
public SimpleTextSiteMapProvider()
{
}
// Implement the CurrentNode property.
public override SiteMapNode CurrentNode
{
get
{
string currentUrl = FindCurrentUrl();
// Find the SiteMapNode that represents the current page.
SiteMapNode currentNode = FindSiteMapNode(currentUrl);
return currentNode;
}
}
// Implement the RootNode property.
public override SiteMapNode RootNode
{
get
{
return rootNode;
}
}
// Implement the ParentProvider property.
public override SiteMapProvider ParentProvider
{
get
{
return parentSiteMapProvider;
}
set
{
parentSiteMapProvider = value;
}
}
// Implement the RootProvider property.
public override SiteMapProvider RootProvider
{
get
{
// If the current instance belongs to a provider hierarchy, it
// cannot be the RootProvider. Rely on the ParentProvider.
if (this.ParentProvider != null)
{
return ParentProvider.RootProvider;
}
// If the current instance does not have a ParentProvider, it is
// not a child in a hierarchy, and can be the RootProvider.
else
{
return this;
}
}
}
// Implement the FindSiteMapNode method.
public override SiteMapNode FindSiteMapNode(string rawUrl)
{
// Does the root node match the URL?
if (RootNode.Url == rawUrl)
{
return RootNode;
}
else
{
SiteMapNode candidate = null;
// Retrieve the SiteMapNode that matches the URL.
lock (this)
{
candidate = GetNode(siteMapNodes, rawUrl);
}
return candidate;
}
}
// Implement the GetChildNodes method.
public override SiteMapNodeCollection GetChildNodes(SiteMapNode node)
{
SiteMapNodeCollection children = new SiteMapNodeCollection();
// Iterate through the ArrayList and find all nodes that have the specified node as a parent.
lock (this)
{
for (int i = 0; i < childParentRelationship.Count; i++)
{
string nodeUrl = ((DictionaryEntry)childParentRelationship[i]).Key as string;
SiteMapNode parent = GetNode(childParentRelationship, nodeUrl);
if (parent != null && node.Url == parent.Url)
{
// The SiteMapNode with the Url that corresponds to nodeUrl
// is a child of the specified node. Get the SiteMapNode for
// the nodeUrl.
SiteMapNode child = FindSiteMapNode(nodeUrl);
if (child != null)
{
children.Add(child as SiteMapNode);
}
else
{
throw new Exception("ArrayLists not in sync.");
}
}
}
}
return children;
}
protected override SiteMapNode GetRootNodeCore()
{
return RootNode;
}
// Implement the GetParentNode method.
public override SiteMapNode GetParentNode(SiteMapNode node)
{
// Check the childParentRelationship table and find the parent of the current node.
// If there is no parent, the current node is the RootNode.
SiteMapNode parent = null;
lock (this)
{
// Get the Value of the node in childParentRelationship
parent = GetNode(childParentRelationship, node.Url);
}
return parent;
}
// Implement the ProviderBase.Initialize property.
// Initialize is used to initialize the state that the Provider holds, but
// not actually build the site map.
public override void Initialize(string name, NameValueCollection attributes)
{
lock (this)
{
base.Initialize(name, attributes);
simpleTextProviderName = name;
sourceFilename = attributes["siteMapFile"];
siteMapNodes = new ArrayList();
childParentRelationship = new ArrayList();
// Build the site map in memory.
LoadSiteMapFromStore();
}
}
// Private helper methods
private SiteMapNode GetNode(ArrayList list, string url)
{
for (int i = 0; i < list.Count; i++)
{
DictionaryEntry item = (DictionaryEntry)list[i];
if ((string)item.Key == url)
return item.Value as SiteMapNode;
}
return null;
}
// Get the URL of the currently displayed page.
private string FindCurrentUrl()
{
try
{
// The current HttpContext.
HttpContext currentContext = HttpContext.Current;
if (currentContext != null)
{
return currentContext.Request.RawUrl;
}
else
{
throw new Exception("HttpContext.Current is Invalid");
}
}
catch (Exception e)
{
throw new NotSupportedException("This provider requires a valid context.",e);
}
}
protected virtual void LoadSiteMapFromStore()
{
string pathToOpen;
lock (this)
{
// If a root node exists, LoadSiteMapFromStore has already
// been called, and the method can return.
if (rootNode != null)
{
return;
}
else
{
pathToOpen = HttpContext.Current.Server.MapPath("~" + "\\" + sourceFilename);
if (File.Exists(pathToOpen))
{
// Open the file to read from.
using (StreamReader sr = File.OpenText(pathToOpen))
{
// Clear the state of the collections and rootNode
rootNode = null;
siteMapNodes.Clear();
childParentRelationship.Clear();
// Parse the file and build the site map
string s = "";
string[] nodeValues = null;
SiteMapNode temp = null;
while ((s = sr.ReadLine()) != null)
{
// Build the various SiteMapNode objects and add
// them to the ArrayList collections. The format used
// is: URL,TITLE,DESCRIPTION,PARENTURL
nodeValues = s.Split(',');
temp = new SiteMapNode(this,
HttpRuntime.AppDomainAppVirtualPath + "/" + nodeValues[0],
HttpRuntime.AppDomainAppVirtualPath + "/" + nodeValues[0],
nodeValues[1],
nodeValues[2]);
// Is this a root node yet?
if (null == rootNode &&
(null == nodeValues[3] || nodeValues[3] == String.Empty))
{
rootNode = temp;
}
// If not the root node, add the node to the various collections.
else
{
siteMapNodes.Add(new DictionaryEntry(temp.Url, temp));
// The parent node has already been added to the collection.
SiteMapNode parentNode =
FindSiteMapNode(HttpRuntime.AppDomainAppVirtualPath + "/" + nodeValues[3]);
if (parentNode != null)
{
childParentRelationship.Add(new DictionaryEntry(temp.Url, parentNode));
}
else
{
throw new Exception("Parent node not found for current node.");
}
}
}
}
}
else
{
throw new Exception("File not found");
}
}
}
return;
}
}
}
コメント
このコード例では、特定の構造に従った SiteMap.txt と呼ばれるコンマ区切りのファイルを使用してサイト マップ情報を読み込みます。ファイルの最初の行はサイト マップのルート ノードを表し、その後の行は子ノードを表します。それぞれの子ノードでは、親ノードを URL で識別します。
default.aspx,Home,MyCompany Home Page,
sale.aspx,Now On Sale,Check Out These Great Deals!,default.aspx
catalog.aspx,Online Catalog,Browse Our Many Great Items!,default.aspx
SimpleTextSiteMapProvider は、SiteMapProvider クラスのすべてのプロパティとメソッドについての実装例です。
最終的に、次のコード例に示すように、SimpleTextSiteMapProvider は、Web.config ファイルの既定のプロバイダとして構成されます。
<configuration>
<system.web>
<siteMap defaultProvider="SimpleTextSiteMapProvider">
<providers>
<add
name="SimpleTextSiteMapProvider"
type="<type name>"
siteMapFile = "<path>/siteMap.txt" />
</providers>
</siteMap>
</system.web>
</configuration>
この例をカスタマイズするには、<type name> を、サイト マップ データ プロバイダを実装する完全修飾名に置き換えます。たとえば、上記の C# コードでは、<type name> を Samples.AspNet.CS.SimpleTextSiteMapProvider に置き換えます。サイト マップ データ プロバイダ コードをコンパイルし、これを Bin ディレクトリに格納する場合、<type name> 文字列にも、コンパイルされたファイルの名前が拡張子なしで含まれている必要があります。たとえば、上記の C# コードを Samples.AspNet.dll というファイルにコンパイルした場合、<type name> を Samples.AspNet.CS.SimpleTextSiteMapProvider.Samples.AspNet に置き換えます。最後に <path> を、サイト マップ ファイルの相対パスに置き換えます。
.gif "メモ") メモ : |
|---|
StaticSiteMapProvider クラスから継承するのではなく、SiteMapProvider クラスから継承する場合は、GetRootNodeCore、FindSiteMapNode、GetChildNodes、および GetParentNode の各メンバをオーバーライドする必要があります。 |