Asp.net(C#)清除所有缓存

清除所有缓存
    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;

    }