protected void RemoveAllCache() 
    { 

       System.Web.Caching.Cache _cache = HttpRuntime.Cache; 
       IDictionaryEnumerator CacheEnum = _cache.GetEnumerator(); 
       ArrayList al = new ArrayList(); 
       while (CacheEnum.MoveNext()) 
       { 
          al.Add(CacheEnum.Key); 
       } 

       foreach (string key in al) 
       { 
          _cache.Remove(key); 
       } 
       show(); 
    } 
//显示所有缓存 
    void show() 
    { 
       string str = ""; 
       IDictionaryEnumerator CacheEnum = HttpRuntime.Cache.GetEnumerator(); 

       while (CacheEnum.MoveNext()) 
       { 
          str += "缓存名<b>[" + CacheEnum.Key+"]</b><br />" ; 
       } 
       this.Label1.Text = "当前网站总缓存数:" + HttpRuntime.Cache.Count + "<br />"+str; 
    }