HttpRuntime.Cache的使用经验

时间:2022-01-18 22:51:26

配置文件

<appSettings>  
<add key="EnableCache" value="true"/>  
<add key="CacheDurationSeconds" value=""/>
</appSettings>

操作方法

代码
using System;
using System.Web.Configuration;
public class SiteHelper
{
    static public object GetCache(string CacheId)
    {
        object objCache = System.Web.HttpRuntime.Cache.Get(CacheId);
        // 判断 Cache 是否启用
        if (WebConfigurationManager.AppSettings["EnableCache"] ==null
            ||!Convert.ToBoolean(WebConfigurationManager.AppSettings["EnableCache"]))
        {
            objCache =null;
            System.Web.HttpRuntime.Cache.Remove(CacheId);
        }
        return objCache;
    }
    ///<summary>
    /// 写入 Cache 资料 ( 预设 60 秒 )
    ///</summary>
    ///<param name="CacheId"></param>
    ///<param name="objCache"></param>
    static public void SetCache(string CacheId, object objCache)
    {
        if (WebConfigurationManager.AppSettings["CacheDurationSeconds"] !=null)
        {
            SetCache(CacheId, objCache, Convert.ToInt32(WebConfigurationManager.AppSettings["CacheDurationSeconds"]));
        }
        else
        {
            SetCache(CacheId, objCache, );
        }
    }
    static public void SetCache(string CacheId, object objCache, int cacheDurationSeconds)
    {
        if (objCache !=null)
        {
            System.Web.HttpRuntime.Cache.Insert(CacheId, objCache, null, System.Web.Caching.Cache.NoAbsoluteExpiration,new TimeSpan(, , cacheDurationSeconds), System.Web.Caching.CacheItemPriority.High, null);
        }
    }
}

使用方法

代码

string strCache1 = SiteHelper.GetCache("Cache1") asstring;
if (strCache1 ==null) {     Response.Write("<p>Cache is empty</p>");
    strCache1 ="OK";     SiteHelper.SetCache("Cache1", strCache1, ); }
Response.Write(strCache1);

常见问题#Cache显示与清空问题

代码

List<string> cacheKeys =new List<string>();
IDictionaryEnumerator cacheEnum = Cache.GetEnumerator();
while (cacheEnum.MoveNext())
{
    cacheKeys.Add(cacheEnum.Key.ToString());
}
foreach (string cacheKey in cacheKeys)
{
    Cache.Remove(cacheKey);
}
代码

    //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;
    }

添加到扩展方法

代码

using System;
using System.Web.Caching;
using System.Collections;
using System.Collections.Generic; ///<summary>
/// 扩充 System.Web.Caching 命名空间的 Extension Methods
///</summary>
static public class CacheExtensionMethod
{
    public static void Clear(this Cache x)
    {
        List<string> cacheKeys =new List<string>();
        IDictionaryEnumerator cacheEnum = x.GetEnumerator();
        while (cacheEnum.MoveNext())
        {
            cacheKeys.Add(cacheEnum.Key.ToString());
        }
        foreach (string cacheKey in cacheKeys)
        {
            x.Remove(cacheKey);
        }
    }
}

转自:http://blog.csdn.net/fengloveyun/article/details/5934158