js compression tool yuicompressor usage tutorial_javascript skills

JS, CSS compression tool yuicompressor 2.46 package provided by Script House
Introduction
Official website: http://developer.yahoo.com/yui/compressor/
JS and CSS compression tool yuicompressor
The latest version: 2.4.2
You need to install JDK first to run, the official download address: http://www.oracle.com/ technetwork/java/javase/downloads/jdk-7u1-download-513651.html Choose the appropriate version according to your own system. Generally, the 586 version is sufficient.
yuicompressor is written in pure Java and requires JDK1.4 or higher to run. It is based on Rhino to analyze and segment JavaScript source files. It can be to remove redundant whitespace characters (spaces, newlines, tabs) in JavaScript files and Css files. For JavaScript files, you can also obfuscate them, change the names of local variables, and change them to a length of 1,2 or 3 characters, in short try to be as short as possible. For CSS, there are also ways to compress files by optimizing the representation of 0-value attribute values ​​and optimizing color values.

Usage Tutorial
The following is an introduction to calling yuicompressor using the command line.
Command line usage
Syntax: java -jar yuicompressor-x.y.z.jar [options] [input file]
Common parameters:
-h, --help display help information
--type < ;js|css> Specify the file type of the input file
--charset Specify the encoding used to read the input file
--line-break Insert a line- after the specified column bread symbol
-v, --verbose displays info and warn level information
-o specifies the output file. The default output is the console.

JavaScript-specific parameters:
--nomunge only compresses, not obfuscates local variables.
--preserve-semi Preserve all semicolons.
--disable-optimizations disables optimizations.

Usage example: java -jar yuicompressor-2.4.2.jar -o d:/temp/hello_min.js hello.js
The following article was written by another netizen, you can For reference.
I wrote a lot of JS code for the website today. Looking at more and more codes, I couldn’t help but panic. This way the website will be very slow. I suddenly remembered that Xiaoma said before that there is a JS compression tool. , so I asked Master A Fei. The enthusiastic Master A Fei passed the tool to me and taught me how to use it. After a try, it turned out to be very good.
This is Yahoo’s yuicompressor, which is very convenient. The usage method is as follows:

Installation steps:

1. Unzip jsMinifier.rar to X:jsMinifier, and add X:jsMinifier to In the system PATH environment variable (if you do not add it to PATH, you can manually modify the registry file, referring to the full path.

2. Rename X:jsMinifierjsMinifier.tpl.reg to jsMinifier.reg, cssMinifier.tpl. reg is cssMinifier.reg. You can modify the configuration yourself (see 1).

3. Run regedt32 to open the registry editor, and then import jsMinifier.reg and cssMinifier.reg into the registry.
Test installation:

1. Right-click on X:jsMinifiertest.source.js and execute the menu "Compress JavaScript". The system will automatically generate the X:jsMinifier test.js file. If you modify test.js again. After the file is compressed once, the system will generate the test-min.js file with unchanged content. This is the default file name for non-source.js file compression.

2. The CSS compression test is similar to 1.

Note: This tool can also compress CSS files
If the file is downloaded from
http://www.jb51.net/jiaoben/25557.html
, download it directly After decompression, just run install.bat. Right-click on the css or js file that needs to be compressed and select
to generate a file with -min after the file name in the same directory. 🎜>
If you need to compress files in batches, you can refer to the script below
Batch processing script sharing under windows (copy to notepad, save as bat, modify the corresponding path to apply):


Copy code

The code is as follows: @echo off ::Set YUI Compressor startup directorySET YUIFOLDER=C:

::Set your JS and CSS root directory, the script will automatically search and compress all JS and CSS according to the tree level

SET JSFOLDER=D:WebJsAndCss
echo is searching JavaScript, CSS ...
chdir /d %JSFOLDER%
for /r . %%a in (*.js *.css) do (
@echo Compressing %%~a ...
@java -jar %YUIFOLDER%yuicompressor-2.4.6.jar --charset UTF-8 %%~fa -o %%~fa
)
echo done!
pause & exi