温故知新ASP.NET 2.0(C#)(3) - SiteMap(站点地图)

using System; 
using System.Web; 
using System.Data.SqlClient; 
using System.Collections.Specialized; 
using System.Configuration; 
using System.Web.Configuration; 
using System.Collections.Generic; 
using System.Configuration.Provider; 
using System.Security.Permissions; 
using System.Data.Common; 
using System.Data; 
 
/// <summary> 
/// SqlSiteMapProvider 
/// </summary> 
public  class SqlSiteMapProvider : StaticSiteMapProvider 
{ 
         private  string _strCon; 
         private  int _indexID, _indexTitle, _indexUrl, _indexDesc, _indexParent; 
 
         // 节点 
         private SiteMapNode _node; 
         
         // 节点字典表 
         private Dictionary< int, SiteMapNode> _nodes =  new Dictionary< int, SiteMapNode>(); 
        
         // for 线程安全 
         private  readonly  object _lock =  new  object(); 
 
         /// <summary> 
         /// 初始化 
         /// </summary> 
         /// <param name="name">name</param> 
         /// <param name="config">config</param> 
         public  override  void Initialize( string name, NameValueCollection config) 
        { 
                 // 验证是否有config 
                 if (config ==  null) 
                         throw  new ArgumentNullException( "config不能是null"); 
 
                 // 没有provider则设置为默认的 
                 if (String.IsNullOrEmpty(name)) 
                        name =  "SqlSiteMapProvider"; 
 
                 // 没有描述就增加一个描述 
                 if ( string.IsNullOrEmpty(config[ "description"])) 
                { 
                        config.Remove( "description"); 
                        config.Add( "description",  "SqlSiteMapProvider"); 
                } 
 
                 // 调用基类的初始化方法 
                 base.Initialize(name, config); 
 
                 // 初始化连接字符串 
                 string conStringName = config[ "connectionStringName"]; 
 
                 if (String.IsNullOrEmpty(conStringName)) 
                         throw  new ProviderException( "没找到connectionStringName"); 
 
                config.Remove( "connectionStringName"); 
 
                 if (WebConfigurationManager.ConnectionStrings[conStringName] ==  null) 
                         throw  new ProviderException( "根据connectionStringName没找到连接字符串"); 
 
                 // 获得连接字符串 
                _strCon = WebConfigurationManager.ConnectionStrings[conStringName].ConnectionString; 
 
                 if (String.IsNullOrEmpty(_strCon)) 
                         throw  new ProviderException( "连接字符串是空的"); 
        } 
 
         /// <summary> 
         /// 从持久性存储区加载站点地图信息，并在内存中构建它 
         /// </summary> 
         /// <returns></returns> 
         public  override SiteMapNode BuildSiteMap() 
        { 
                 lock (_lock) 
                { 
                         // 线程安全的实现 
                         if (_node !=  null) 
                                 return _node; 
 
                        SqlConnection connection =  new SqlConnection(_strCon); 
 
                         try 
                        { 
                                SqlCommand command =  new SqlCommand( "sp_GetSiteMap", connection); 
                                command.CommandType = CommandType.StoredProcedure; 
 
                                connection.Open(); 
                                SqlDataReader reader = command.ExecuteReader(); 
 
                                 // 获得各个字段的索引 
                                _indexID = reader.GetOrdinal( "ID"); 
                                _indexUrl = reader.GetOrdinal( "Url"); 
                                _indexTitle = reader.GetOrdinal( "Title"); 
                                _indexDesc = reader.GetOrdinal( "Description"); 
                                _indexParent = reader.GetOrdinal( "Parent"); 
 
                                 if (reader.Read()) 
                                { 
                                         // 把第一条记录作为根节点添加 
                                        _node = CreateSiteMapNodeFromDataReader(reader); 
                                        AddNode(_node,  null); 
 
                                         // 构造节点树 
                                         while (reader.Read()) 
                                        { 
                                                 // 在站点地图中增加一个节点 
                                                SiteMapNode node = CreateSiteMapNodeFromDataReader(reader); 
                                                AddNode(node, GetParentNodeFromDataReader(reader)); 
                                        } 
 
                                } 
 
                                reader.Close(); 
                        } 
                         catch (Exception ex) 
                        { 
                                 throw  new Exception(ex.ToString()); 
                        } 
                         finally 
                        { 
                                connection.Close(); 
                        } 
 
                         // 返回SiteMapNode 
                         return _node; 
                } 
        } 
 
         /// <summary> 
         /// 将检索目前由当前提供程序管理的所有节点的根节点 
         /// </summary> 
         /// <returns></returns> 
         protected  override SiteMapNode GetRootNodeCore() 
        { 
                 lock (_lock) 
                { 
                         return BuildSiteMap(); 
                } 
        } 
 
         /// <summary> 
         /// 根据DataReader读出来的数据返回SiteMapNode 
         /// </summary> 
         /// <param name="reader">DbDataReader</param> 
         /// <returns></returns> 
         private SiteMapNode CreateSiteMapNodeFromDataReader(DbDataReader reader) 
        { 
                 if (reader.IsDBNull(_indexID)) 
                         throw  new ProviderException( "没找到ID"); 
 
                 int id = reader.GetInt32(_indexID); 
 
                 if (_nodes.ContainsKey(id)) 
                         throw  new ProviderException( "不能有重复ID"); 
 
                 // 根据字段索引获得相应字段的值 
                 string title = reader.IsDBNull(_indexTitle) ?  null : reader.GetString(_indexTitle).Trim(); 
                 string url = reader.IsDBNull(_indexUrl) ?  null : reader.GetString(_indexUrl).Trim(); 
                 string description = reader.IsDBNull(_indexDesc) ?  null : reader.GetString(_indexDesc).Trim(); 
 
                 // 新建一个SiteMapNode 
                SiteMapNode node =  new SiteMapNode( this, id.ToString(), url, title, description); 
 
                 // 把这个SiteMapNode添加进节点字典表里 
                _nodes.Add(id, node); 
 
                 // 返回这个SiteMapNode 
                 return node; 
        } 
 
         /// <summary> 
         /// 得到父节点的SiteMapNode 
         /// </summary> 
         /// <param name="reader"></param> 
         /// <returns></returns> 
         private SiteMapNode GetParentNodeFromDataReader(DbDataReader reader) 
        { 
                 if (reader.IsDBNull(_indexParent)) 
                         throw  new ProviderException( "父节点不能是空"); 
 
                 int pid = reader.GetInt32(_indexParent); 
 
                 if (!_nodes.ContainsKey(pid)) 
                         throw  new ProviderException( "有重复节点ID"); 
 
                 // 返回父节点的SiteMapNode 
                 return _nodes[pid]; 
        } 
 
 
}

<configuration> 
    <appSettings/> 
    <connectionStrings> 
        <add name="SqlConnectionString" connectionString="Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\Database.mdf;Integrated Security=True;User Instance=True"/> 
    </connectionStrings> 
    <system.web> 
        <siteMap enabled="true" defaultProvider="XmlSiteMapProvider"> 
            <providers> 
                <add name="XmlSiteMapProvider" type="System.Web.XmlSiteMapProvider, System.Web, Version=2.0.3600.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a" siteMapFile="~/Web.sitemap"/> 
                <add name="XmlSiteMapProviderTest" type="System.Web.XmlSiteMapProvider, System.Web, Version=2.0.3600.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a" siteMapFile="~/Sitemap/Web.sitemap"/> 
                <add name="SqlSiteMapProvider" type="SqlSiteMapProvider" connectionStringName="SqlConnectionString" /> 
            </providers> 
        </siteMap> 
    </system.web> 
</configuration>