验证URL中GUID值是否重复的类库，防止用户直截刷URL(代码存在问题，一直没找到来。看有没有高人能看出来。)

验证URL中GUID值是否重复的类库，防止用户直截刷URL，设计思路如下：

定义了两个队列：

当前写入队列 Hashtable writeTb

备份队列 Hashtable readTb

已经使用过的GUID值记录在writeTb,readTb列表中。

当新的GUID值上来的时候，判断writeTb,readTb队列中是否存在GUID值，如果存在，就判断为非法。

两个队列根据一定的间隔时间来轮换切读写。当readTb切换成写队列的时候。readTb中记录的GUID值全部清除。

 

直接上代码：(代码是存在问题的，没跑多久的时候CPU就100%了，一直找不到问题，看看有没有高人能看出问题所在)

 

  1 public class RequestValidate
  2     {
  3         private Thread clearTbWorker = null;
  4         private Hashtable tb1 = new Hashtable(100000);
  5         private Hashtable tb2 = new Hashtable(100000);
  6 
  7         /// <summary>
  8         /// 上次转换TB时间
  9         /// </summary>
 10         private DateTime lastSwitchTbTime { get; set; }
 11 
 12         /// <summary>
 13         /// 写TB索引
 14         /// </summary>
 15         private int writeTbIndex{get;set;}
 16 
 17         /// <summary>
 18         /// 当前写入队列
 19         /// </summary>
 20         private Hashtable writeTb
 21         {
 22             get
 23             {
 24                 if (writeTbIndex == 1) return tb1;
 25                 else return tb2;
 26             }
 27         }
 28 
 29         /// <summary>
 30         /// 备份队列
 31         /// </summary>
 32         private Hashtable readTb
 33         {
 34             get
 35             {
 36                 if (writeTbIndex == 1) return tb2;
 37                 else return tb1;
 38             }
 39         }
 40 
 41         private HttpRequest request { get { return HttpContext.Current.Request; } }
 42 
 43         /// <summary>
 44         /// GUID受限使用时间
 45         /// </summary>
 46         private TimeSpan GuidExpiredMinute = TimeSpan.FromMinutes(2);
 47 
 48         private RequestValidate()
 49         {
 50             lastSwitchTbTime = System.DateTime.Now;
 51             clearTbWorker = new Thread(new ThreadStart(ClearTbWork));
 52             clearTbWorker.Start();
 53         }
 54 
 55         private static RequestValidate instance = null;
 56         public static RequestValidate Instance
 57         {
 58             get
 59             {
 60                 if (instance == null)
 61                 {
 62                     lock (typeof(RequestValidate))
 63                     {
 64                         if (instance == null)
 65                         {
 66                             instance = new RequestValidate();
 67                         }
 68                     }
 69                 }
 70                 return instance;
 71             }
 72         }
 73 
 74         /// <summary>
 75         /// 验证客户端GUID值是否合法
 76         /// </summary>
 77         /// <returns></returns>
 78         public bool Validate()
 79         {
 80             string guid = request["guid"];
 81             if (string.IsNullOrEmpty(guid))
 82             {
 83 #if DEBUG
 84                 return false;
 85 #else
 86                 return true;
 87 #endif
 88             }
 89 
 90             if (!string.IsNullOrEmpty(request["t"]))
 91             {
 92                 HttpContext.Current.Response.ContentType = "text/html";
 93                 HttpContext.Current.Response.Write("readTb:"+readTb.Count);
 94                 HttpContext.Current.Response.Write("writeTb:" + this.writeTb.Count);
 95                 HttpContext.Current.Response.End();
 96             }
 97 
 98             bool isTrue = true;
 99 
100             try
101             {
102                 string htKey = guid.ToLower();
103                 if (readTb.ContainsKey(htKey))
104                 {
105                     isTrue = false;
106                 }
107                 else if (writeTb.ContainsKey(htKey))
108                 {
109                     isTrue = false;
110                 }
111                 else
112                 {
113                     writeTb[htKey] = System.DateTime.Now;
114                 }
115             }
116             catch (Exception ex)
117             {
118                 Log.LogComplement.Error(ex);
119             }
120 
121             return isTrue;
122 
123         }
124 
125         /// <summary>
126         /// 清除过期队列
127         /// </summary>
128         private void ClearTbWork()
129         {
130             while (true)
131             {
132                 try
133                 {
134 
135 
136                     TimeSpan ts = System.DateTime.Now - lastSwitchTbTime;
137                     if (ts < GuidExpiredMinute)
138                     {
139                         System.Threading.Thread.Sleep(ts);
140                     }
141 
142                     //清除GuidExpiredMinute分钟之前备份队列
143                     readTb.Clear();
144 
145                     if (writeTbIndex == 1) writeTbIndex = 2;
146                     else writeTbIndex = 1;
147 
148                     lastSwitchTbTime = System.DateTime.Now;
149 
150                     
151 
152                 }
153                 catch (Exception ex)
154                 {
155                     Log.LogComplement.Error(ex);
156                 }
157                 finally
158                 {
159                     System.Threading.Thread.Sleep(GuidExpiredMinute);
160                 }
161             }
162 
163         }
164         
165     }