本文實(shí)例講述了asp.net程序優(yōu)化js、css實(shí)現(xiàn)合并與壓縮的方法。分享給大家供大家參考。具體實(shí)現(xiàn)方法如下：
    訪問(wèn)時(shí)將js和css壓縮并且緩存在客戶端,
    采用的是yahoo.yui.compressor組件來(lái)完成的,用戶可以點(diǎn)擊此處本站下載。
    創(chuàng)建一個(gè)ihttphandler來(lái)處理文件
    代碼如下:
    public class combinefiles : ihttphandler
    {
    private const string cachekeyformat = _cachekey_{0}_;
    private const bool iscompress = true; //需要壓縮
    public bool isreusable
    {
    get
    {
    return false;
    }
    }
    public void processrequest(httpcontext context)
    {
    httprequest request = context.request;
    httpresponse response = context.response;
    string cachekey = string.empty;
    string type = request.querystring[type];
    if (!string.isnullorempty(type) && (type == css || type == js))
    {
    if (type == js)
    {
    response.contenttype = text/javascript;
    }
    else if (type == css)
    {
    response.contenttype = text/css;
    }
    cachekey = string.format(cachekeyformat, type);
    compresscacheitem cacheitem = httpruntime.cache[cachekey] as compresscacheitem;
    if (cacheitem == null)
    {
    string content = string.empty;
    string path = context.server.mappath();
    //找到這個(gè)目錄下所有的js或css文件，當(dāng)然也可以進(jìn)行配置，需求請(qǐng)求壓縮哪些文件
    //這里就將所的有文件都請(qǐng)求壓縮
    string[] files = directory.getfiles(path, *. + type);
    stringbuilder sb = new stringbuilder();
    foreach (string filename in files)
    {
    if (file.exists(filename))
    {
    string readstr = file.readalltext(filename, encoding.utf8);
    sb.append(readstr);
    }
    }
    content = sb.tostring();
    // 開(kāi)始?jí)嚎s文件
    if (iscompress)
    {
    if (type.equals(js))
    {
    content = javascriptcompressor.compress(content);
    }
    else if (type.equals(css))
    {
    content = csscompressor.compress(content);
    }
    }
    //輸入到客戶端還可以進(jìn)行g(shù)zip壓縮 ,這里就省略了
    cacheitem = new compresscacheitem() { type = type, content = content, expires = datetime.now.adddays(30) };
    httpruntime.cache.insert(cachekey, cacheitem, null, cacheitem.expires, timespan.zero);
    }
    string ifmodifiedsince = request.headers[if-modified-since];
    if (!string.isnullorempty(ifmodifiedsince)
    && timespan.fromticks(cacheitem.expires.ticks - datetime.parse(ifmodifiedsince).ticks).seconds < 0)
    {
    response.statuscode = (int)system.net.httpstatuscode.notmodified;
    response.statusdescription = not modified;
    }
    else
    {
    response.write(cacheitem.content);
    setclientcaching(response, cacheitem.expires);
    }
    }
    }
    private void setclientcaching(httpresponse response, datetime expires)
    {
    response.cache.setetag(datetime.now.ticks.tostring());
    response.cache.setlastmodified(datetime.now);
    //public 以指定響應(yīng)能由客戶端和共享（代理）緩存進(jìn)行緩存。
    response.cache.setcacheability(httpcacheability.public);
    //是允許文檔在被視為陳舊之前存在的最長(zhǎng)絕對(duì)時(shí)間。
    response.cache.setmaxage(timespan.fromticks(expires.ticks));
    response.cache.setslidingexpiration(true);
    }
    private class compresscacheitem
    {
    /// <summary>
    /// 類型 js 或 css
    /// </summary>
    public string type { get; set; } // js css
    /// <summary>
    /// 內(nèi)容
    /// </summary>
    public string content { set; get; }
    /// <summary>
    /// 過(guò)期時(shí)間
    /// </summary>
    public datetime expires { set; get; }
    }
    }
    最后在配置文件中配置一下combinefiles.axd文件，具體配置略
    引用如下
    復(fù)制代碼 代碼如下:<script type=text/javascript src=/js/combinefiles.axd?type=js></script>
    <link rel=stylesheet type=text/css href=/css/combinefiles.axd?type=css />
    希望本文所述對(duì)大家的asp.net程序設(shè)計(jì)有所幫助。