Web应用程序系统的多用户权限控制设计及实现-登录模块【4】

通过前三个模块的介绍，把web权限系统开发所需要的基本类，Css文件，EasyUI框架等准备好后，就可以着手开始系统的编码了。

登陆模块是权限处理系统的关键，根据输入用户的的信息，可自动从数据库中加载该用户可以访问的页面，匹配出可以操作的模块。

由于登录模块是系统的基本模块，因此没有单独放在一个域里面。登录的控制器在项目默认的Controllers文件夹下。登录对应的视图在项目默认的Views文件夹下。

1.1视图

登录视图中比较重要的是通过.NET MVC的Ajax异步方式提交用户名和密码到后台服务。

提交格式如下：@using (Ajax.BeginForm("Login", "Login",
                            new AjaxOptions
                            {
                                OnBegin = "loginBefore",
                                OnSuccess = "showMessage"
                            }))

在提交数据前做必要的数据格式校验，提交成功后，通过Login.js文件中的函数跳转到首页。登录模块的详细视图内容如下：

  1 @{
  2     Layout = null;
  3 }
  4 
  5 <!DOCTYPE html>
  6 
  7 <html>
  8 <head>
  9     <meta name="viewport" content="width=device-width" />
 10     <title>用户登录</title>
 11     <script src="~/Scripts/jquery-1.7.1.js"></script>
 12     <link href="~/Content/css/login.css" rel="stylesheet" />
 13     <link href="~/Content/easyui143/themes/bootstrap/easyui.css" rel="stylesheet" />
 14     <style type="text/css">
 15         .passwordtxt {
 16             height: 35px;
 17             width: 117px;
 18             line-height: 27px;
 19             border: none;
 20             border: none;
 21             font-size: 14px;
 22             text-indent: 10px;
 23             background: url(../../Content/images/passwordtxt.png);
 24             vertical-align: middle;
 25             color: black;
 26             margin-left: 5px;
 27         }
 28 
 29 
 30         .inputicon {
 31             margin-left: -410px;
 32             vertical-align: middle;
 33         }
 34 
 35         .btn, .yzm {
 36             cursor: pointer;
 37         }
 38 
 39 
 40         .txtfocus {
 41             height: 42px;
 42             width: 262px;
 43             line-height: 27px;
 44             border: none;
 45             border: none;
 46             font-size: 14px;
 47             text-indent: 10px;
 48             background: url(../../Content/images/inputing.png) no-repeat;
 49             vertical-align: middle;
 50             color: black;
 51         }
 52 
 53 
 54         .passwordfocustxt {
 55             height: 35px;
 56             width: 117px;
 57             line-height: 27px;
 58             border: none;
 59             border: none;
 60             font-size: 14px;
 61             text-indent: 10px;
 62             background: url(../../Content/images/checkcodeinputing.png);
 63             vertical-align: middle;
 64             color: black;
 65             margin-left: 5px;
 66         }
 67     </style>
 68     <script src="~/Scripts/jquery.unobtrusive-ajax.min.js"></script>
 69 
 70 </head>
 71 <body>
 72     <div class="all">
 73         <div class="loginContent">
 74             <div class="loginContent-inner">
 75                 <h1 class="loginTitle"></h1>
 76                 <div class="main">
 77                     <div class="erro">
 78                     </div>
 79                     <ul class="loginList">
 80                         @using (Ajax.BeginForm("Login", "Login", 
 81                             new AjaxOptions
 82                             {
 83                                 OnBegin = "loginBefore",
 84                                 OnSuccess = "showMessage"
 85                             }))
 86                         {
 87                             <li>
 88                                 <span>用户名</span>
 89                                 <input type="text" tabindex="1" class="txt" name="userName" id="UserName" style="padding-left: 35px;" />
 90                                 <input type="submit" name="LoginBut" class="btn" value="登录" style="border-width: 0px;" onclick=" return Login();" />
 91                                 <img src="/Content/Images/user1.png" class="inputicon" id="userNameImg" />
 92                             </li>
 93                      
 94                             <li>
 95                                 <span>密&nbsp;&nbsp;码</span>
 96                                 <input name="password" id="Password" type="password" tabindex="2" class="txt" style="padding-left: 35px;" />
 97                                 <input type="button" onclick="javascript: Cancel();" class="submit" value="重置" style="border: 0px; cursor: pointer;" />
 98                                 <img src="/Content/Images/password1.png" class="inputicon" id="passwordImg" />
 99                             </li>
100                             <li>
101                                 <span>验证码</span>
102                                 <input type="text" tabindex="3" name="checkCode" id="txtCheckCode" class="passwordtxt" />
103                                 <img src="/ValidateCode/ValidateCode" id="CheckImage"
104                                     onclick="ChangeCode()" width="69" height="27" class="yzm" />
105                                 <a href="javascript:ChangeCode();" style="color: #00689d; text-decoration: underline;">换一张</a>
106                             </li>
107                         }
108                     </ul>
109                 </div>
110                 <div class="loginFooter">
111                     支持FireFox、IE8及其以上版本的浏览器       
112                     <br />
113                     技术支持：######<span></span>
114                 </div>
115                 @if (ViewData["AA"] == null)
116                 {
117                     <div>                      
118                     </div>
119                 }
120             </div>
121         </div>
122     </div>
123 
124     <script type="text/javascript" src="~/Scripts/CustomJs/login.js">
125     </script>
126 
127 </body>
128 </html>

1.2 JS文件

登录模块所用的JS文件在项目的根目录Scripts目录下。它主要是提交登录信息，根据服务器返回的结果判断登录信息是否有效。详细的JS代码如下：

  1 //显示遮罩层
  2 function LoadMask(msg) {
  3     var panel = $("body");
  4     if (msg == undefined) {
  5         msg = "正在登陆，请稍候...";
  6     }
  7     $("<div class=\"datagrid-mask\"></div>").css({ display: "block", width: panel.width(), height: panel.height() }).appendTo(panel);
  8     $("<div class=\"datagrid-mask-msg\"></div>").html(msg).appendTo(panel).css({ display: "block", left: (panel.width() - $("div.datagrid-mask-msg", panel).outerWidth()) / 2, top: (panel.height() - $("div.datagrid-mask-msg", panel).outerHeight()) / 2 });
  9 };
 10 
 11 //隐藏遮罩层
 12 function HideMask() {
 13     var panel = $("body");
 14     panel.find("div.datagrid-mask-msg").remove();
 15     panel.find("div.datagrid-mask").remove();
 16 };
 17 
 18 //刷新验证码
 19 function ChangeCode() {
 20     $("#CheckImage").prop("src", "/ValidateCode/ValidateCode/" + Math.ceil(Math.random() * 1000));
 21     $("#txtCheckCode").val("");
 22 };
 23 
 24 //前台验证用户输入信息
 25 function Login() {
 26     if ($("#UserName").val().replace(/ /g, "") == "") {
 27         alert("请输入帐号！");
 28         return false;
 29     }
 30     if ($("#Password").val().replace(/ /g, "") == "") {
 31         alert("请输入密码！");
 32         return false;
 33     }
 34 
 35     if ($("#txtCheckCode").val().replace(/ /g, "") == "") {
 36         alert("请输入验证码！");
 37         return false;
 38     }
 39     return true;
 40 }
 41 
 42 //重置，清空用户已经输入的信息
 43 function Cancel() {
 44     $("#UserName").val("");
 45     $("#Password").val("");
 46     $("#txtCheckCode").val("");
 47     ChangeCode();
 48 }
 49 
 50 function loginBefore() {
 51     if ($("#UserName").val().replace(/ /g, "") == "") {
 52         alert("请输入帐号！");
 53         return false;
 54     }
 55     if ($("#Password").val().replace(/ /g, "") == "") {
 56         alert("请输入密码！");
 57         return false;
 58     }
 59 
 60     if ($("#txtCheckCode").val().replace(/ /g, "") == "") {
 61         alert("请输入验证码！");
 62         return false;
 63     }
 64     LoadMask();
 65     return true;
 66 };
 67 
 68 //将用户信息提交到后台，经后台验证后的操作，回调函数
 69 function showMessage(data) {
 70     HideMask();
 71     if (data == "1") {
 72         window.location.href = "/IndexHome/IndexHome";
 73     }
 74     else {
 75         alert(data);
 76         $("#Password").val("");
 77         //刷新验证码
 78         ChangeCode();
 79     }
 80 }
 81 
 82 
 83 $(function () {
 84 
 85     $("#UserName").focus(function () {
 86         $(this).removeClass("txt");
 87         $(this).addClass("txtfocus");
 88         $("#userNameImg").attr("src", "/Content/Images/user2.png");
 89     }).blur(function () {
 90         $(this).removeClass("txtfocus");
 91         $(this).addClass("txt");
 92         $("#userNameImg").attr("src", "/Content/Images/user1.png");
 93     });
 94 
 95 
 96     $("#Password").focus(function () {
 97         $(this).removeClass("txt");
 98         $(this).addClass("txtfocus");
 99         $("#passwordImg").attr("src", "/Content/Images/password2.png");
100     }).blur(function () {
101         $(this).removeClass("txtfocus");
102         $(this).addClass("txt");
103         $("#passwordImg").attr("src", "/Content/Images/password1.png");
104     });
105 
106     $("#txtCheckCode").focus(function () {
107         $(this).removeClass("passwordtxt");
108         $(this).addClass("passwordfocustxt");
109     }).blur(function () {
110         $(this).removeClass("passwordfocustxt");
111         $(this).addClass("passwordtxt");
112     });
113 
114 
115 });

1.3 控制器

登录控制器是整个权限处理的核心模块，它根据用户的信息自动加载出用户可以访问的目录信息，可以访问的网页信息通过Session的方式，把信息通过SessionManage基本类进行会话管理。部分代码如下：

SessionManage.CurrentUser = null;先清空会话信息

#region 封装用户信息

   var currentUser = new AccountInfo();
                currentUser.OperatorId = Convert.ToString(dr["accountid"]);
                currentUser.OperatorName = DBNull.Value.Equals(dr["accountname"]) ? "" : Convert.ToString(dr["accountname"]);
                currentUser.AliasName = DBNull.Value.Equals(dr["aliasname"]) ? "" : Convert.ToString(dr["aliasname"]);
                currentUser.Sex = DBNull.Value.Equals(dr["sex"]) ? "" : (Convert.ToInt32(dr["sex"]) == 0 ? "男" : "女");
                currentUser.OperatorGroupId = DBNull.Value.Equals(dr["groupid"]) ? "" : Convert.ToString(dr["groupid"]);
                currentUser.OperatorGroupName = (string.IsNullOrEmpty(groupName) ? "" : groupName.Substring(0, groupName.Length - 1));

SessionManage.CurrentUser = currentUser; //保存基本信息
#endregion

   //目录列表（存储登录人员可以访问的一级目录和访问的网页）
                IList<Catalog> navigationList = new List<Catalog>();
                IList<Catalog> rightList = new List<Catalog>();

控制器的完整代码如下：

  1 using System;
  2 using System.Collections.Generic;
  3 using System.Linq;
  4 using System.Web;
  5 using System.Web.Mvc;
  6 using Session;
  7 using OdbcDbAccess;
  8 using System.Data;
  9 using Models;
 10 using LogInfo;
 11 
 12 namespace CqReportSystem
 13 {
 14     public class LoginController : Controller
 15     {
 16         /// <summary>
 17         /// ****************************
 18         /// 功能：登陆类
 19         /// 作者：王令
 20         /// 时间：2015-7-18
 21         /// 邮箱：1129137758@qq.com
 22         /// ****************************
 23         
 24         public ActionResult Login()
 25         {
 26             SessionManage.CurrentUser = null;
 27             Session.Clear();
 28             return View();
 29         }
 30 
 31         /// <summary>
 32         /// 用户登陆信息验证
 33         /// </summary>
 34         /// <param name="userName">账号</param>
 35         /// <param name="password">密码</param>
 36         /// <param name="checkCode">验证码</param>
 37         /// <returns></returns>
 38         [HttpPost]
 39         public ContentResult Login(string userName, string password, string checkCode)
 40         {
 41             #region 不为空、验证码验证
 42 
 43             if (string.IsNullOrEmpty(userName) || userName.Trim() == "")
 44             {
 45                 return Content("请输入用户名！");
 46             }
 47             if (string.IsNullOrEmpty(password) || password.Trim() == "")
 48             {
 49                 return Content("请输入登陆密码！");
 50             }
 51             if (string.IsNullOrEmpty(checkCode) || checkCode.Trim() == "")
 52             {
 53                 return Content("请输入验证码！");
 54             }
 55             if (Session["CheckCode"] == null)
 56             {
 57                 Log.SaveLoginLog(0, "验证码过期");
 58                 return Content("验证码已过期,请刷新验证码！");
 59             }
 60             if (String.Compare(Session["CheckCode"].ToString(), checkCode, true) != 0)
 61             {
 62                 Log.SaveLoginLog(0, "验证码有误");
 63                 return Content("验证码有误！");
 64             }
 65             #endregion
 66 
 67             //移除验证码信息
 68             Session.Remove("CheckCode");
 69             string sql = "select * from operatorinfo where accountid='" + userName.Trim() + "' and passwords='" + password.Trim() + "' ";
 70             try
 71             {
 72                 string groupName = "";
 73                 #region 基本信息判断
 74                 //判断用户名和密码是否正确
 75                 DataSet dataSet = SqlHelper.ExecuteQuery(ConnectionHelper.GeSqlDbConnectionStr(), sql);
 76                 if (dataSet == null || dataSet.Tables.Count < 1 || dataSet.Tables[0].Rows.Count < 1)
 77                 {
 78                      Log.SaveLoginLog(0, "用户名或密码有误");
 79                     return Content("用户名或密码有误！");
 80                 }
 81                 //账号是否启用
 82                 DataRow dr = dataSet.Tables[0].Rows[0];
 83                 if (DBNull.Value.Equals(dr["isonstaff"]) || Convert.ToInt32(dr["isonstaff"]) != 1)
 84                 {
 85                     Log.SaveLoginLog(0, "该账号未启用");
 86                     return Content("该账号未启用！");
 87                 }
 88                 //查找用户所属组
 89                 sql = "select groupname,state from operatorgroup where groupid in (" + Convert.ToString(dr["groupid"]) + ")";
 90                 DataSet groupSet = SqlHelper.ExecuteQuery(ConnectionHelper.GeSqlDbConnectionStr(), sql);
 91                 if (groupSet == null || groupSet.Tables.Count < 1 || groupSet.Tables[0].Rows.Count < 1)
 92                 {
 93                     Log.SaveLoginLog(0, "未找到该用户所属用户组");
 94                     return Content("未找到该用户所属用户组！");
 95                 }
 96 
 97                 foreach (DataRow groupRow in groupSet.Tables[0].Rows)
 98                 {
 99                     if (DBNull.Value.Equals(groupRow["state"]) || Convert.ToInt32(groupRow["state"]) != 1)
100                     {
101                         Log.SaveLoginLog(0, "该用户所属用户组未被启用");
102                         return Content("该用户所属用户组未被启用！");
103                     }
104                     if (!DBNull.Value.Equals(groupRow["groupname"]))
105                     {
106                         groupName += Convert.ToString(groupRow["groupname"]) + ",";
107                     }
108                 }
109 
110                 #endregion
111                 var currentUser = new AccountInfo();
112                 #region 封装用户信息 
113                 currentUser.OperatorId = Convert.ToString(dr["accountid"]);
114                 currentUser.OperatorName = DBNull.Value.Equals(dr["accountname"]) ? "" : Convert.ToString(dr["accountname"]);
115                 currentUser.AliasName = DBNull.Value.Equals(dr["aliasname"]) ? "" : Convert.ToString(dr["aliasname"]);
116                 currentUser.Sex = DBNull.Value.Equals(dr["sex"]) ? "" : (Convert.ToInt32(dr["sex"]) == 0 ? "男" : "女");
117                 currentUser.OperatorGroupId = DBNull.Value.Equals(dr["groupid"]) ? "" : Convert.ToString(dr["groupid"]);
118                 currentUser.OperatorGroupName = (string.IsNullOrEmpty(groupName) ? "" : groupName.Substring(0, groupName.Length - 1));
119                 #endregion
120                 SessionManage.CurrentUser = currentUser;
121                 //验证通过，设置用户权限
122                 if (!SetOperatorRight(currentUser.OperatorGroupId, currentUser.OperatorId))
123                 {
124                     Log.SaveLoginLog(0, "权限设置失败");
125                     return Content("权限设置失败！");
126                 }
127 
128                Log.SaveLoginLog(1, "登陆成功");
129 
130                 return Content("1");
131             }
132             catch (Exception ex)
133             {
134                 Log.SaveLoginLog(0, ex.ToString());
135                 return Content("服务器内部错误！");
136             }
137         }
138 
139         /// <summary>
140         /// 设置用户权限
141         /// </summary>
142         /// <param name="operatorGroupId">用户组ID</param>
143         /// <param name="operatorId">用户登录账号</param>
144         /// <returns></returns>
145         private bool SetOperatorRight(string operatorGroupId, string operatorId)
146         {
147             try
148             {
149                 //目录列表
150                 IList<Catalog> navigationList = new List<Catalog>();
151                 IList<Catalog> rightList = new List<Catalog>();
152              
153                 //获取首级导航栏信息
154                 string strSql = "select distinct parentid,parentcatalogname,parentshowno from (select a.catalogid,a.parentid,b.parentid as granparendid," +
155                                 "a.catalogname,b.catalogname as parentcatalogname,a.showno,b.showno as parentshowno ,b.isavailable from catalog a left join  " +
156                                 "catalog b on a.parentid=b.catalogid) as temptable where granparendid=0 and  isavailable=1 and catalogid in (select categoryid from rightlist " +
157                                 "where operatorgroupid in (" + operatorGroupId + ")) order by parentshowno";          
158                 DataSet navigationDs = SqlHelper.ExecuteQuery(ConnectionHelper.GeSqlDbConnectionStr(), strSql);
159                 if (navigationDs != null && navigationDs.Tables.Count > 0 && navigationDs.Tables[0].Rows.Count > 0)
160                 {
161                     #region 封装导航栏到List
162 
163                     foreach (DataRow row in navigationDs.Tables[0].Rows)
164                     {
165                         int parentId = DBNull.Value.Equals(row["parentid"]) ? 0 : Convert.ToInt32(row["parentid"]);
166                         string parentName = DBNull.Value.Equals(row["parentcatalogname"]) ? "" : Convert.ToString(row["parentcatalogname"]);
167 
168                         var item = new Catalog
169                         {
170                             CatalogId = parentId,
171                             ParentId = 0,
172                             CatalogName = parentName
173                         };
174                         navigationList.Add(item);
175                     }
176 
177                     #endregion
178 
179                     #region 获取二级栏目信息及页面信息
180 
181                     //获取二级分类信息
182                     strSql = "select * from catalog where catalogid in (select categoryid from rightlist where operatorgroupid in (" +
183                         operatorGroupId + ")) and isavailable=1 order by showno";
184                     DataSet catalogDs = SqlHelper.ExecuteQuery(ConnectionHelper.GeSqlDbConnectionStr(), strSql);
185                     //获取页面信息
186                     strSql = "select * from pageinfo where pageid in ( select pageid from rightlist where operatorgroupid in (" +
187                         operatorGroupId + ")) and isavailable=1 order by catalogid,showno";
188                     DataSet pageDs = SqlHelper.ExecuteQuery(ConnectionHelper.GeSqlDbConnectionStr(), strSql);
189 
190                     //无栏目，则返回false
191                     if (catalogDs == null || catalogDs.Tables.Count <= 0 || catalogDs.Tables[0].Rows.Count <= 0)
192                     {
193                         return false;
194                     }
195                     //无权限页面，则返回false
196                     if (pageDs == null || pageDs.Tables.Count <= 0 || pageDs.Tables[0].Rows.Count <= 0)
197                     {
198                         return false;
199                     }
200 
201                     #endregion
202                     #region 封装用户权限
203 
204                     DataTable catalogTb = catalogDs.Tables[0];
205                     DataTable pageTb = pageDs.Tables[0];
206 
207                     foreach (DataRow catalogDr in catalogTb.Rows)
208                     {
209                         int catalogId = Convert.ToInt32(catalogDr["catalogid"]);
210                         int parentId = Convert.ToInt32(catalogDr["parentid"]);
211                         string catalogName = Convert.ToString(catalogDr["catalogname"]);
212                         string picUrl = DBNull.Value.Equals(catalogDr["picurl"]) ? "" : Convert.ToString(catalogDr["picurl"]);
213                         var catalogItem = new Catalog { CatalogId = catalogId, ParentId = parentId, CatalogName = catalogName, PictureUrl = picUrl, PageList = new List<Page>() };
214 
215                         //获取目录下的页面行
216                         DataRow[] pageRows = pageTb.Select("catalogid=" + catalogId);
217                         if (pageRows.Length > 0)
218                         {
219                             foreach (DataRow pageDr in pageRows)
220                             {
221                                 int pageId = Convert.ToInt32(pageDr["pageid"]);
222                                 string pageName = Convert.ToString(pageDr["pagename"]);
223                                 string pageUrl = Convert.ToString(pageDr["pageurl"]);
224                                 var pageItem = new Page { PageIndex = pageId, PageName = pageName, PageUrl = pageUrl, CategoryId = catalogId };
225                                 catalogItem.PageList.Add(pageItem);
226                             }
227                         }
228                         rightList.Add(catalogItem);
229                     }
230                     #endregion
231                     AccountInfo info = SessionManage.CurrentUser;
232                     info.NavigationList = navigationList;
233                     info.RightList = rightList;
234                     SessionManage.CurrentUser = info;
235                     return true;
236                 }
237                 return false;
238             }
239             catch (Exception e1)
240             {
241                 Log.SaveErrorLog(e1.ToString(), "设置用户权限出错");
242                 return false;
243             }
244         }
245     }
246 }

LoginController.cs

1.4界面运行截图

1.5验证码生成控制器

验证码的处理方式也是一个控制器，它对应一个视图页面。视图页面中不需要编写代码，只是需要视图这个文件。供登录模块调用。对于视图的生成，只需要右键ValidateCode，点击添加视图就可以了。

public ActionResult ValidateCode()
        {
            CreateCheckCodeImage(GenerateCheckCode());
            return View();
        }

验证码生成的控制器代码如下：

  1 using System;
  2 using System.Collections.Generic;
  3 using System.Drawing;
  4 using System.Linq;
  5 using System.Web;
  6 using System.Web.Mvc;
  7 
  8 namespace Controllers
  9 {
 10     /// <summary>
 11     /// ****************************
 12     /// 功能：验证码
 13     /// 作者：王令
 14     /// 时间：2015-7-01
 15     /// 邮箱：1129137758@qq.com
 16     /// ****************************
 17     
 18     public class ValidateCodeController : Controller
 19     {
 20         public ActionResult ValidateCode()
 21         {
 22             CreateCheckCodeImage(GenerateCheckCode());
 23             return View();
 24         }
 25 
 26 
 27         /// <summary>
 28         /// 生成验证码
 29         /// </summary>
 30         /// <returns></returns>
 31         private string GenerateCheckCode()
 32         {
 33             int number;
 34             char code;
 35             string checkCode = String.Empty;
 36             System.Random random = new Random();
 37 
 38             bool F = true;
 39             while (F)
 40             {
 41                 number = random.Next();
 42                 if (number % 2 == 0)
 43                     code = (char)('0' + (char)(number % 10));
 44                 else
 45                     code = (char)('A' + (char)(number % 26));
 46 
 47                 if (code == '0' || code == 'O' || code == '1' || code == 'I' || code == '2' || code == 'Z')
 48                 {
 49                     //排序0、O、1、L等字符
 50                 }
 51                 else
 52                 {
 53                     checkCode += code.ToString();
 54                     if (checkCode.Length == 4)
 55                     {
 56                         F = false;
 57                     }
 58                 }
 59             }
 60 
 61             Session.Add("CheckCode", checkCode);
 62             return checkCode;
 63         }
 64 
 65 
 66 
 67         /// <summary>
 68         /// 生成验证码图片
 69         /// </summary>
 70         /// <param name="checkCode"></param>
 71         private void CreateCheckCodeImage(string checkCode)
 72         {
 73             if (checkCode == null || checkCode.Trim() == String.Empty)
 74                 return;
 75             System.Drawing.Bitmap image = new System.Drawing.Bitmap((int)Math.Ceiling((checkCode.Length * 12.5)), 22);
 76             Graphics g = Graphics.FromImage(image);
 77 
 78             try
 79             {
 80                 //生成随机生成器
 81                 Random random = new Random();
 82 
 83                 //清空图片背景色
 84                 g.Clear(Color.White);
 85 
 86                 //画图片的背景噪音线
 87                 for (int i = 0; i < 25; i++)
 88                 {
 89                     int x1 = random.Next(image.Width);
 90                     int x2 = random.Next(image.Width);
 91                     int y1 = random.Next(image.Height);
 92                     int y2 = random.Next(image.Height);
 93                     g.DrawLine(new Pen(Color.Silver), x1, y1, x2, y2);
 94                 }
 95                 //
 96                 Font font = new System.Drawing.Font("Arial", 12, (System.Drawing.FontStyle.Bold | System.Drawing.FontStyle.Italic));
 97                 System.Drawing.Drawing2D.LinearGradientBrush brush = new System.Drawing.Drawing2D.LinearGradientBrush(new Rectangle(0, 0, image.Width, image.Height), Color.Blue, Color.DarkRed, 1.2f, true);
 98                 g.DrawString(checkCode, font, brush, 2, 2);
 99 
100                 //画图片的前景噪音点
101                 for (int i = 0; i < 100; i++)
102                 {
103                     int x = random.Next(image.Width);
104                     int y = random.Next(image.Height);
105                     image.SetPixel(x, y, Color.FromArgb(random.Next()));
106                 }
107 
108                 //画图片的边框线
109                 g.DrawRectangle(new Pen(Color.Silver), 0, 0, image.Width - 1, image.Height - 1);
110                 System.IO.MemoryStream ms = new System.IO.MemoryStream();
111                 image.Save(ms, System.Drawing.Imaging.ImageFormat.Gif);
112                 Response.ClearContent();
113                 Response.ContentType = "image/Gif";
114                 Response.BinaryWrite(ms.ToArray());
115             }
116 
117             finally
118             {
119                 g.Dispose();
120                 image.Dispose();
121 
122             }
123         }
124 
125     }
126 }