基于.net的principal、identity接口的用户处理机制.
SiteIdentity.cs using System;
using System.Text;
using System.Collections;
using System.Security.Cryptography;
namespace ContextUser 
{
    
    /// <summary> 
    /// SiteIdentity 的摘要说明. 
    /// </summary> 
    public class SiteIdentity: System.Security.Principal.IIdentity 
    {
        private string userName;
        private string emailAddress;
        private int userID;
        
        public SiteIdentity( string currentUserName ) 
        {
            userName = currentUserName;
            emailAddress = "test@msn.com";
            userID = 1;
        }
        public string AuthenticationType 
        {
            get 
            {
                return "Custom Authentication";
            }
            set 
            {
                
                // do nothing 
            }
        }
        public bool IsAuthenticated 
        {
            get 
            {
                // assumption: all instances of a SiteIdentity have already
                // been authenticated. return true;
            }
        }
        public string Name 
        {
            get 
            {
                return userName;
            }
        }
        public string EmailAddress 
        {
            get 
            {
                return emailAddress;
            }
        }
        public int UserID 
        {
            get 
            {
                return userID;
            }
        }
    }
}
----------------------------------------------------------------------------------------------- SitePrincipal.cs using System;
using System.Collections;
using System.Security;
using System.Security.Cryptography;
namespace ContextUser 
{
    /// <summary> 
    /// SitePrincipal 的摘要说明. 
    /// </summary> 
    public class SitePrincipal: System.Security.Principal.IPrincipal 
    {
        protected System.Security.Principal.IIdentity identity;
        protected ArrayList permissionList;
        //许可动态数组 protected ArrayList roleList;
        //角色动态数组
        public System.Security.Principal.IIdentity Identity 
        {
            get 
            {
                return identity;
            }
            set 
            {
                identity = value;
            }
        }
        public SitePrincipal( string username )//构造函数逻辑 
        {
            identity = new SiteIdentity( username );
            roleList = new ArrayList( );
            //添加角色数组 以后可以用从数据库获取数值代替 roleList.Add( "Admin" );
            roleList.Add( "123" );
            permissionList = new ArrayList( );
            permissionList.Add( 2 );
            //permissionList = dataUser.GetEffectivePermissionList( userID );
            //roleList = dataUser.GetUserRoles( userID );
        }
        public static SitePrincipal ValidateLogin( string username, string password )//验证登陆 
        {
            if( username == "1111111" && password == "1111111" )//可以用从数据库验证替代 
            {
                return new SitePrincipal( username );
            }
            else 
            {
                return null;
            }
        }
        
        public bool IsInRole( string role ) 
        {
            return roleList.Contains( role );
        }
        
        public bool HasPermission( int permissionID ) 
        {
            return permissionList.Contains( permissionID );
        }
        public ArrayList Roles 
        {
            get 
            {
                return roleList;
            }
        }
        public ArrayList Permissions 
        {
            get 
            {
                return permissionList;
            }
        }
    }
}
 下面继承page 用于需要验证的页面继承
BasePage.cs using System;
using System.Web;
using System.Web.UI;
using System.Diagnostics;
namespace ContextUser 
{
    
    /// <summary> 
    /// BasePage 的摘要说明. 
    /// </summary> 
    public class BasePage : System.Web.UI.Page 
    {
        
        public BasePage( ) 
        {
        }
        
        protected override void OnInit( EventArgs e ) 
        {
            base.OnInit( e );
            this.Load += new System.EventHandler( this.BasePage_Load );
        }
        
        private void BasePage_Load( object sender, System.EventArgs e ) 
        {
            if ( Context.User.Identity.IsAuthenticated ) 
            {
                if ( !( Context.User is SitePrincipal ) ) 
                {
                    Response.Write( "Context.User.Identity.Is Authenticated" );
                    SitePrincipal newUser = new SitePrincipal( Context.User.Identity.Name );
                    Context.User = newUser;
                    Response.Write( Context.User.IsInRole( "123" ) );
                }
            }
        }
    }
}
-------------------------------------------------------------------------- 登陆页面
using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Web;
using System.Web.Security;
using System.Web.SessionState;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.HtmlControls;
namespace ContextUser 
{
    
    /// <summary> 
    /// WebForm1 的摘要说明. 
    /// </summary> 
    public class WebForm1 : ContextUser.BasePage 
    {
        protected System.Web.UI.WebControls.TextBox username;
        protected System.Web.UI.WebControls.TextBox pwd;
        protected System.Web.UI.WebControls.Label Label1;
        protected System.Web.UI.WebControls.Label Label2;
        protected System.Web.UI.WebControls.Button Button1;
        
        private void Page_Load( object sender, System.EventArgs e ) 
        {
            // 在此处放置用户代码以初始化页面 
            
        }
        #region Web 窗体设计器生成的代码 override 
        protected void OnInit( EventArgs e ) 
        {
            //
            // CODEGEN: 该调用是 ASP.NET Web 窗体设计器所必需的.
            // InitializeComponent( );
            base.OnInit( e );
        }
        /// <summary> 
        /// 设计器支持所需的方法 - 不要使用代码编辑器修改 
        /// 此方法的内容. 
        /// </summary> 
        private void InitializeComponent( ) 
        {
            this.Button1.Click += new System.EventHandler( this.Button1_Click );
            this.Load += new System.EventHandler( this.Page_Load );
        }
        #endregion 
        private void Button1_Click( object sender, System.EventArgs e ) 
        {
            SitePrincipal principal = SitePrincipal.ValidateLogin( username.Text, pwd.Text );
            if( principal == null ) 
            {
                Label1.Text = "用户名或密码不正确";
            }
            else 
            {
                Context.User = principal;
                FormsAuthentication.SetAuthCookie( username.Text, true );
                if( Context.User.IsInRole( "123" ) ) 
                {
                    Label2.Text = "用户" + Context.User.Identity.Name + "属于Admin组";
                }
                else 
                {
                    Label2.Text = "用户" + Context.User.Identity.Name + "不属于Admin组";
                }
            }
        }
    }
}
--------------------------------------------------- 验证页面 需要继承basepage using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Web;
using System.Web.SessionState;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.HtmlControls;
namespace ContextUser 
{
    
    /// <summary> 
    /// _default 的摘要说明. 
    /// </summary> 
    public class _default : ContextUser.BasePage 
    {
        protected System.Web.UI.WebControls.Label Label1;
        
        private void Page_Load( object sender, System.EventArgs e ) 
        {
            if ( !Context.User.Identity.IsAuthenticated || !( ( SitePrincipal )Context.User ).HasPermission( 2 ) ) 
            {
                Page.Response.Redirect( "WebForm1.aspx" );
            }
            else 
            {
                Page.Response.Write( "通过" );
            }
        }
        #region Web 窗体设计器生成的代码 override 
        protected void OnInit( EventArgs e ) 
        {
            //
            // CODEGEN: 该调用是 ASP.NET Web 窗体设计器所必需的.
            // base.OnInit( e );
            //------------------------------------------------------------注意这里需要放在上边 InitializeComponent( );
        }
        /// <summary> 
        /// 设计器支持所需的方法 - 不要使用代码编辑器修改 
        /// 此方法的内容. 
        /// </summary> 
        private void InitializeComponent( ) 
        {
            this.Load += new System.EventHandler( this.Page_Load );
        }
        #endregion 
    }
}