discuz!nt里的投票代码

可能要写一个投票系统，把discuz！net里面的代码放到这里来参考参考，感觉它的投票功能做的有点简单，数据库里面相关的就两个主从表，不过想想也可以理解，毕竟是论坛里的投票小功能，没太复杂的需求。

/// <summary>
   /// 投票操作类
   /// </summary>
   public class Polls
   {

       /// <summary>
       /// 创建一个投票
       /// </summary>
       /// <param name="tid">关联的主题id</param>
       /// <param name="multiple">投票类型, 0为单选, 1为多选</param>
       /// <param name="itemcount">投票项总数</param>
       /// <param name="itemnamelist">投票项目列表</param>
       /// <param name="itemvaluelist">投票项目结果列表</param>
       /// <param name="usernamelist">用户名列表</param>
       /// <param name="enddatetime">截止日期</param>
       /// <param name="userid">用户id</param>
       /// <param name="maxchoices">最多可选项数</param>
       /// <param name="visible">提交投票后结果才可见, 0为可见, 1为投票后可见</param>
       /// <returns>成功则返回true, 否则返回false</returns>
       public static bool CreatePoll(int tid, int multiple, int itemcount, string itemnamelist, string itemvaluelist, string enddatetime, int userid, int maxchoices, int visible)
       {
           string[] itemname = Utils.SplitString(itemnamelist, "\r\n");
           string[] itemvalue = Utils.SplitString(itemvaluelist, "\r\n");
           if ((itemname.Length != itemcount) || (itemvalue.Length != itemcount))
           {
               return false;
           }

           PollInfo pollinfo = new PollInfo();
           pollinfo.Displayorder = 0;
           pollinfo.Expiration = Utils.GetStandardDateTime(enddatetime);
           pollinfo.Maxchoices = maxchoices;
           pollinfo.Multiple = multiple;
           pollinfo.Tid = tid;
           pollinfo.Uid = userid;
           pollinfo.Visible = visible;

           int pollid = DatabaseProvider.GetInstance().CreatePoll(pollinfo);

           if (pollid > 0)
           {
               for (int i = 0; i < itemcount; i++)
               {
                   PollOptionInfo polloptioninfo = new PollOptionInfo();
                   polloptioninfo.Displayorder = i + 1;
                   polloptioninfo.Pollid = pollid;
                   polloptioninfo.Polloption = Utils.GetSubString(itemname[i], 80, "");
                   polloptioninfo.Tid = tid;
                   polloptioninfo.Voternames = "";
                   polloptioninfo.Votes = 0;
                   DatabaseProvider.GetInstance().CreatePollOption(polloptioninfo);
               }
               return true;
           }
           else
           {
               return false;
           }
       }

       /// <summary>
       /// 更新一个投票
       /// </summary>
       /// <param name="tid">关联的主题id</param>
       /// <param name="multiple">投票类型, 0为单选, 1为多选</param>
       /// <param name="itemcount">投票项总数</param>
       /// <param name="polloptionidlist">投票项id列表</param>
       /// <param name="itemnamelist">投票项目列表</param>
       /// <param name="itemdisplayorderlist">投票项目排列顺序列表</param>
       /// <param name="enddatetime">截止日期</param>
       /// <param name="maxchoices">最多可选项数</param>
       /// <param name="visible">提交投票后结果才可见, 0为可见, 1为投票后可见</param>
       /// <returns>成功则返回true, 否则返回false</returns>
       public static bool UpdatePoll(int tid, int multiple, int itemcount, string polloptionidlist, string itemnamelist, string itemdisplayorderlist, string enddatetime, int maxchoices, int visible)
       {
           //
           string[] itemname = Utils.SplitString(itemnamelist, "\r\n");
           string[] itemdisplayorder = Utils.SplitString(itemdisplayorderlist, "\r\n");
           string[] polloptionid = Utils.SplitString(polloptionidlist, "\r\n");

           if ((itemname.Length != itemcount) || (itemdisplayorder.Length != itemcount))
           {
               return false;
           }

           PollInfo pollinfo = GetPollInfo(tid);
           pollinfo.Expiration = Utils.GetStandardDateTime(enddatetime);
           pollinfo.Maxchoices = maxchoices;
           pollinfo.Multiple = multiple;
           pollinfo.Tid = tid;
           pollinfo.Visible = visible;

           bool result = false;
           if (pollinfo.Pollid > 0)
           {
               result = DatabaseProvider.GetInstance().UpdatePoll(pollinfo);
           }
           if (result)
           {
               PollOptionInfoCollection polloptioninfocoll = GetPollOptionInfoCollection(pollinfo.Tid);
               int i = 0;

               //先作已存在的投票选项更新及新添加选项的添加操作
               bool optionexist;
               foreach (string optionid in polloptionid)
               {
                   optionexist = false;
                   foreach (PollOptionInfo polloptioninfo in polloptioninfocoll)
                   {
                       if (optionid == polloptioninfo.Polloptionid.ToString())
                       {
                           polloptioninfo.Pollid = pollinfo.Pollid;
                           polloptioninfo.Polloption = Utils.GetSubString(itemname[i], 80, "");
                           polloptioninfo.Displayorder = Utils.StrIsNullOrEmpty(itemdisplayorder[i]) ? i + 1 : Utils.StrToInt(itemdisplayorder[i], 0);
                           DatabaseProvider.GetInstance().UpdatePollOption(polloptioninfo);
                           optionexist = true;
                           break;
                       }
                   }
                   if (!optionexist) //如果当前选项不存在，表示该选项为新添选项
                   {
                       PollOptionInfo polloptioninfo = new PollOptionInfo();
                       polloptioninfo.Displayorder = Utils.StrIsNullOrEmpty(itemdisplayorder[i]) ? i + 1 : Utils.StrToInt(itemdisplayorder[i], 0);
                       polloptioninfo.Pollid = pollinfo.Pollid;
                       polloptioninfo.Polloption = Utils.GetSubString(itemname[i], 80, "");
                       polloptioninfo.Tid = tid;
                       polloptioninfo.Voternames = "";
                       polloptioninfo.Votes = 0;
                       DatabaseProvider.GetInstance().CreatePollOption(polloptioninfo);
                   }
                   i++;
               }

               foreach (PollOptionInfo polloptioninfo in polloptioninfocoll)
               {
                   //下面代码用于删除已去除的投票项
                   if (("\r\n" + polloptionidlist + "\r\n").IndexOf("\r\n" + polloptioninfo.Polloptionid + "\r\n") < 0)
                   {
                       DatabaseProvider.GetInstance().DeletePollOption(polloptioninfo);
                   }
               }

               return true;
           }
           else
           {
               return false;
           }
       }

       /// <summary>
       /// 通过主题ID获取相应的投票信息
       /// </summary>
       /// <param name="tid">投票主题的id</param>
       /// <returns>投票信息</returns>
       public static PollInfo GetPollInfo(int tid)
       {
           PollInfo pollinfo = new PollInfo();
           IDataReader idatareader = DatabaseProvider.GetInstance().GetPollList(tid);
           while (idatareader.Read())
           {
               pollinfo.Pollid = Utils.StrToInt(idatareader["pollid"], 0);
               pollinfo.Displayorder = Utils.StrToInt(idatareader["displayorder"], 0);
               pollinfo.Expiration = Utils.GetStandardDate(idatareader["expiration"].ToString());
               pollinfo.Maxchoices = Utils.StrToInt(idatareader["maxchoices"], 0);
               pollinfo.Multiple = Utils.StrToInt(idatareader["multiple"], 0);
               pollinfo.Tid = Utils.StrToInt(idatareader["tid"], 0);
               pollinfo.Visible = Utils.StrToInt(idatareader["visible"], 0);
               pollinfo.Voternames = idatareader["voternames"].ToString().Trim();
               break; //目前一个主题只有一个投票，因此在绑定了第一条投票信息后退出
           }
           idatareader.Close();
           return pollinfo;
       }

       /// <summary>
       /// 通过主题ID获取相应的投票信息
       /// </summary>
       /// <param name="tid">主题id</param>
       /// <returns>投票选项集合</returns>
       public static PollOptionInfoCollection GetPollOptionInfoCollection(int tid)
       {
           PollOptionInfoCollection pollinfocoll = new PollOptionInfoCollection();
           IDataReader idatareader = DatabaseProvider.GetInstance().GetPollOptionList(tid);
           PollOptionInfo polloptioninfo;
           while (idatareader.Read())
           {
               polloptioninfo = new PollOptionInfo();
               polloptioninfo.Polloptionid = Utils.StrToInt(idatareader["polloptionid"], 0);
               polloptioninfo.Displayorder = Utils.StrToInt(idatareader["displayorder"], 0);
               polloptioninfo.Pollid = Utils.StrToInt(idatareader["pollid"], 0);
               polloptioninfo.Polloption = idatareader["polloption"].ToString().Trim();
               polloptioninfo.Tid = Utils.StrToInt(idatareader["tid"], 0);
               polloptioninfo.Voternames = idatareader["voternames"].ToString().Trim();
               polloptioninfo.Votes = Utils.StrToInt(idatareader["votes"], 0);
               pollinfocoll.Add(polloptioninfo);
           }
           idatareader.Close();
           return pollinfocoll;
       }

       /// <summary>
       /// 根据投票信息更新数据库中的记录
       /// </summary>
       /// <param name="tid">主题id</param>
       /// <param name="selitemidlist">选择的投票项id列表</param>
       /// <param name="username">用户名</param>
       /// <returns>如果执行成功则返回0, 非法提交返回负值</returns>
       public static int UpdatePoll(int tid, string selitemidlist, string username)
       {
           if (username == "")
           {
               return -1;
           }

           string[] selitemid = Utils.SplitString(selitemidlist, ",");
           int nowid = 0;
           foreach (string optionid in selitemid)
           {
               nowid = Utils.StrToInt(optionid, -1);
               // 如果id结果集合中出现非数字类型字符则认为是非法
               if (nowid == -1)
               {
                   return -1;
               }
           }

           PollInfo pollinfo = GetPollInfo(tid);

           if (pollinfo.Pollid < 1)
           {
               return -3;
           }

           if (Utils.StrIsNullOrEmpty(pollinfo.Voternames))
           {
               pollinfo.Voternames = username;
           }
           else
           {
               pollinfo.Voternames = pollinfo.Voternames + "\r\n" + username;
           }

           DatabaseProvider.GetInstance().UpdatePoll(pollinfo);
           PollOptionInfoCollection polloptioninfocoll = GetPollOptionInfoCollection(pollinfo.Tid);

           foreach (string optionid in selitemid)
           {
               foreach (PollOptionInfo polloptioninfo in polloptioninfocoll)
               {
                   if (optionid == polloptioninfo.Polloptionid.ToString())
                   {
                       if (Utils.StrIsNullOrEmpty(polloptioninfo.Voternames))
                       {
                           polloptioninfo.Voternames = username;
                       }
                       else
                       {
                           polloptioninfo.Voternames = polloptioninfo.Voternames + "\r\n" + username;
                       }
                       polloptioninfo.Votes += 1;
                       DatabaseProvider.GetInstance().UpdatePollOption(polloptioninfo);
                   }
               }
           }

           return 0;
       }

       /// <summary>
       /// 获得与指定主题id关联的投票数据
       /// </summary>
       /// <param name="tid">主题id</param>
       /// <returns>投票数据</returns>
       public static DataTable GetPollOptionList(int tid)
       {

           DataTable dt = new DataTable();
           dt.Columns.Add("name", System.Type.GetType("System.String"));//投票项名称
           dt.Columns.Add("value", System.Type.GetType("System.String"));//票数
           dt.Columns.Add("barid", System.Type.GetType("System.Int32"));
           dt.Columns.Add("barwidth", System.Type.GetType("System.Double"));//显示宽度
           dt.Columns.Add("percent", System.Type.GetType("System.String"));//投票百分比
           dt.Columns.Add("multiple", System.Type.GetType("System.String"));//是否多选
           dt.Columns.Add("polloptionid", System.Type.GetType("System.Int32"));//投票项ID
           dt.Columns.Add("displayorder", System.Type.GetType("System.Int32"));//排序位置
           dt.Columns.Add("votername", System.Type.GetType("System.String"));//投票人名称
           dt.Columns.Add("percentwidth", System.Type.GetType("System.String"));//投票进度条宽度
           PollOptionInfoCollection polloptioninfocoll = GetPollOptionInfoCollection(tid);
           object[] rowVals;

           int multiple = GetPollInfo(tid).Multiple;

           int votesum = 0;
           int maxVote = 0;
           foreach (PollOptionInfo polloptioninfo in polloptioninfocoll)
           {
               votesum += polloptioninfo.Votes;
               maxVote = polloptioninfo.Votes > maxVote ? polloptioninfo.Votes : maxVote;
           }
           if (votesum == 0)
           {
               votesum = 1;
           }
           int i = 0;
           string votername = "";
           //组定数据项
           foreach (PollOptionInfo polloptioninfo in polloptioninfocoll)
           {
               rowVals = new object[10];
               rowVals[0] = polloptioninfo.Polloption;
               rowVals[1] = polloptioninfo.Votes;
               rowVals[2] = i % 10;
               rowVals[3] = (((double)(Utils.StrToFloat(polloptioninfo.Votes, 0) * 100 / votesum) / 100) * 200 + 3).ToString("0.00");
               rowVals[4] = ((double)(Utils.StrToFloat(polloptioninfo.Votes, 0) * 100 / votesum) / 100).ToString("0.00%");
               rowVals[5] = multiple;
               rowVals[6] = polloptioninfo.Polloptionid;
               rowVals[7] = polloptioninfo.Displayorder;

               if (!Utils.StrIsNullOrEmpty(polloptioninfo.Voternames))
               {
                   //将投票人字段的数据重新组合成链接字符串
                   foreach (string username in Utils.SplitString(polloptioninfo.Voternames, "\r\n"))
                   {
                       votername += "<a href=\"userinfo.aspx?username=" + Utils.UrlEncode(username.Trim()) + "\">" + username.Trim() + "</a> ";
                   }
                   rowVals[8] = votername;
                   votername = "";
               }
               else
               {
                   rowVals[8] = "";
               }
               rowVals[9] = (420*((double) (Utils.StrToFloat(polloptioninfo.Votes, 0)/maxVote))).ToString();
               dt.Rows.Add(rowVals);
               i++;
           }
           return dt;
       }

       /// <summary>
       /// 判断是否允许指定用户投票
       /// </summary>
       /// <param name="tid">主题id</param>
       /// <param name="username">用户名</param>
       /// <returns>判断结果</returns>
       public static bool AllowVote(int tid, string username)
       {
           if (username == "")
           {
               return false;
           }
           string strUsernamelist = DatabaseProvider.GetInstance().GetPollUserNameList(tid);

           // 如果已投票用户uid列表为"" (尚无人投票), 则立即返回true
           if (strUsernamelist.Equals(""))
           {
               return true;
           }

           // 检查已投票用户uid列表中是否存在指定用户的uid
           string[] usernamelist = Utils.SplitString(strUsernamelist.Trim(), "\r\n");
           int itemcount = usernamelist.Length;
           for (int i = 0; i < itemcount; i++)
           {
               if (usernamelist[i].Trim() == username)
               {
                   return false;
               }
           }
           return true;
       }

       /// <summary>
       /// 获取参与投票者名单
       /// </summary>
       /// <param name="tid">投票的主题id</param>
       /// <param name="userid">当前投票用户id</param>
       /// <param name="username">当前投票用户名</param>
       /// <param name="allowvote">是否允许投票</param>
       /// <returns>参与投票者名单</returns>
       public static string GetVoters(int tid, int userid, string username, out bool allowvote)
       {
           string strUsernamelist = DatabaseProvider.GetInstance().GetPollUserNameList(tid);
           // 如果已投票用户uid列表为"" (尚无人投票), 则立即返回true
           allowvote = true;
           if (strUsernamelist.Equals(""))
           {
               return "";
           }
           string[] votername = Utils.SplitString(strUsernamelist.Trim(), "\r\n");
           StringBuilder sbVoters = new StringBuilder();
           for (int i = 0; i < votername.Length; i++)
           {
               if (votername[i].Trim() == username)
               {
                   allowvote = false;
               }

               if (userid == -1 && Utils.InArray(tid.ToString(), ForumUtils.GetCookie("dnt_polled")))
               {
                   allowvote = false;
               }

               if (votername[i].IndexOf(' ') == -1)
               {
                   sbVoters.Append("<a href=\"userinfo.aspx?username=");
                   sbVoters.Append(Utils.UrlEncode(votername[i].Trim()));
                   sbVoters.Append("\">");
                   sbVoters.Append(votername[i]);
                   sbVoters.Append("</a>");
               }
               else
               {
                   sbVoters.Append(votername[i].Substring(0, votername[i].LastIndexOf(".") + 1).Trim().Replace(" ", string.Empty) + "]");
               }
               sbVoters.Append("&nbsp; ");
           }

           return sbVoters.ToString();
       }

       /// <summary>
       /// 得到投票帖的投票类型
       /// </summary>
       /// <param name="tid">主题ID</param>
       /// <returns>投票类型</returns>
       public static int GetPollType(int tid)
       {
           return DatabaseProvider.GetInstance().GetPollType(tid);
       }

       /// <summary>
       /// 得到投票帖的结束时间
       /// </summary>
       /// <param name="tid">主题id</param>
       /// <returns>结束时间</returns>
       public static string GetPollEnddatetime(int tid)
       {
           return DatabaseProvider.GetInstance().GetPollEnddatetime(tid);
       }

   }