Ajax Tutorial，Ajax指導

from: http://www.readablog.com/feed23650.aspx

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The

main problem when we are using

ajax

framework

is because of their big size. Of course, it will

extremely slow down the sites load time. For example, if we use the

standard

jQuery

,

it’s almost 100Kb. It’s even more if we use the complete

Prototype and Scriptaculous

that will cost around 150Kb.

在我們使用ajax架構的時候，最讓我們困擾的就是這些架構檔案太多了。是以，載入這些檔案會非常的慢。例如：如果使用標準的（即不經壓縮的）jQuery，檔案達到100Kb大小。完整的Prototype和Scriptaculous加起來更是達到了150Kb。

This

is really nightmare for people who still use GPRS

or the old 56kbps

Dial-Up

internet connection. It will takes minutes to load the sites or maybe

it will takes forever because the browser usually won’t download

it. Unfortunately, it’s very easy to solve this problem. Do you

know that we can compress those files and reduce the size by half or

more?

這對仍然使用GPRS或56kbps撥號上網的用戶來講，簡直就是夢魘。這將花去流覽器很多時間去下載甚至永遠都不會下載這些網站文檔，因為流覽器通常會不下載這樣大的檔案。很不幸的是，其實解決這個問題是非常簡單的（說不幸，又說很簡單，呃……）。你知道嗎？我們可以把這些檔案壓縮或者是減小到一半甚至一半以下！

There

are several method to compress

javascript

and I think one of the most efficient method is using

Gzip

Compression.

在許多壓縮javascript的辦法當中，我最讓為效果最好的就是使用Gzip壓縮法了。

To

implement the gzip

compression

for websites, first we need to gzip

the Javascript files. For that purpose, we will need a

gzip-compatible archiver / compressor.

7-zip

is my favorite because it’s small, very fast and it’s completely

free.

使用Gzip壓縮法，首先，我們要把Javascript檔案壓縮為gzip檔案。（要把檔案壓縮為Gzip檔案，就要使用到Gzip相容的壓縮工具，作者在此做一下廣告：7-zip壓縮工具，不但體積小，運行快，並且是完全免費的！）

the JavaScript file, change the “gz”

extension to “jgz”

for safari

compatibility

and upload it to the same location together with the original script.

Then next, we must ask apache to get the compressed version if there

is available

and finally tell the browser to un-compress the file before it can be

used.

把javascipt檔壓縮後，把副檔名由“gz”改為“jgz”（，以便for

safari

compatibility？不明白

compatibility是什麽）。然後把所有壓縮前及壓縮後的.jgz與js檔上傳到相同路徑。然後，我們還得配置apache，讓它把壓縮的版本（？？）發給客戶端，這樣，流覽器就會知道哪些檔案會在使用前需要進行壓縮。

do that, we add these following code in our .htaccess

這一步操作就是把以下這段代碼加入到.htaccess文檔中：

RewriteEngine on RewriteCond %{HTTP:Accept-Encoding} gzip RewriteCond %{REQUEST_FILENAME}.jgz -f RewriteRule (.*).js$ $1.js.jgz [L] AddType “text/javascript” .js.jgz AddEncoding gzip .jgz

That’s

all. Yeah.. And if you want to look for another method this is it.:

這樣就可以了，哦耶！你也可以參照與這種方法相似其實方法：

• Joseph

  Scott’s Blog

  - Compressed JavaScript
• rakaz

  - Make your pages load faster by combining and compressing

  javascript and css files

• Added

  Bytes

  - PHP, Gzip and htaccess

• Let

  me have a blog

  - Using GZIP compression in web servers using

  .HTACCESS

• Apache

  Module

  - mod_deflate
• mod_gzip

  - Internet Content Acceleration module for the popular Apache Web

  Server