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。