这篇文章主要介绍了php实现压缩合并js的方法,涉及php压缩文件类JSMin的相关调用与使用技巧,并附带了完整的demo源码供读者下载参考,需要的朋友可以参考下
test.php文件如下：
require_once('jsmin.php');
$files = glob("js/*.js");
$js = "";
foreach($files as $file) {
$js .= JSMin::minify(file_get_contents($file));
}
file_put_contents("combined.js", $js);
echo "success";jsmin.php文件如下：
<?php
/**
* jsmin.php - PHP implementation of Douglas Crockford's JSMin.
*
* This is pretty much a direct port of jsmin.c to PHP with just a few
* PHP-specific performance tweaks. Also, whereas jsmin.c reads from stdin and
* outputs to stdout, this library accepts a string as input and returns another
* string as output.
*
* PHP 5 or higher is required.
*
* Permission is hereby granted to use this version of the library under the
* same terms as jsmin.c, which has the following license:
*
* --
* Copyright (c) 2002 Douglas Crockford (www.crockford.com)
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of
* this software and associated documentation files (the "Software"), to deal in
* the Software without restriction, including without limitation the rights to
* use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
* of the Software, and to permit persons to whom the Software is furnished to do
* so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* The Software shall be used for Good, not Evil.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
* --
*
* @package JSMin
* @author Ryan Grove <ryan@wonko.com>
* @copyright 2002 Douglas Crockford <douglas@crockford.com> (jsmin.c)
* @copyright 2008 Ryan Grove <ryan@wonko.com> (PHP port)
* @copyright 2012 Adam Goforth <aag@adamgoforth.com> (Updates)
* @license http://opensource.org/licenses/mit-license.php MIT License
* @version 1.1.2 (2012-05-01)
* @link https://github.com/rgrove/jsmin-php
*/
class JSMin {
const ORD_LF = 10;
const ORD_SPACE = 32;
const ACTION_KEEP_A = 1;
const ACTION_DELETE_A = 2;
const ACTION_DELETE_A_B = 3;
protected $a = '';
protected $b = '';
protected $input = '';
protected $inputIndex = 0;
protected $inputLength = 0;
protected $lookAhead = null;
protected $output = '';
// -- Public Static Methods --------------------------------------------------
/**
* Minify Javascript
*
* @uses __construct()
* @uses min()
* @param string $js Javascript to be minified
* @return string
*/
public static function minify($js) {
$jsmin = new JSMin($js);
return $jsmin->min();
}
// -- Public Instance Methods ------------------------------------------------
/**
* Constructor
*
* @param string $input Javascript to be minified
*/
public function __construct($input) {
$this->input = str_replace("\r\n", "\n", $input);
$this->inputLength = strlen($this->input);
}
// -- Protected Instance Methods ---------------------------------------------
/**
* Action -- do something! What to do is determined by the $command argument.
*
* action treats a string as a single character. Wow!
* action recognizes a regular expression if it is preceded by ( or , or =.
*
* @uses next()
* @uses get()
* @throws JSMinException If parser errors are found:
* - Unterminated string literal
* - Unterminated regular expression set in regex literal
* - Unterminated regular expression literal
* @param int $command One of class constants:
* ACTION_KEEP_A Output A. Copy B to A. Get the next B.
* ACTION_DELETE_A Copy B to A. Get the next B. (Delete A).
* ACTION_DELETE_A_B Get the next B. (Delete B).
*/
protected function action($command) {
switch($command) {
case self::ACTION_KEEP_A:
$this->output .= $this->a;
case self::ACTION_DELETE_A:
$this->a = $this->b;
if ($this->a === "'" || $this->a === '"') {
for (;;) {
$this->output .= $this->a;
$this->a = $this->get();
if ($this->a === $this->b) {
break;
}
if (ord($this->a) <= self::ORD_LF) {
throw new JSMinException('Unterminated string literal.');
}
if ($this->a === '\\') {
$this->output .= $this->a;
$this->a = $this->get();
}
}
}
case self::ACTION_DELETE_A_B:
$this->b = $this->next();
if ($this->b === '/' && (
$this->a === '(' || $this->a === ',' || $this->a === '=' ||
$this->a === ':' || $this->a === '[' || $this->a === '!' ||
$this->a === '&' || $this->a === '|' || $this->a === '?' ||
$this->a === '{' || $this->a === '}' || $this->a === ';' ||
$this->a === "\n" )) {
$this->output .= $this->a . $this->b;
for (;;) {
$this->a = $this->get();
if ($this->a === '[') {
/*
inside a regex [...] set, which MAY contain a '/' itself. Example: mootools Form.Validator near line 460:
return Form.Validator.getValidator('IsEmpty').test(element) || (/^(?:[a-z0-9!#$%&'*+/=?^_`{|}~-]\.?){0,63}[a-z0-9!#$%&'*+/=?^_`{|}~-]@(?:(?:[a-z0-9](?:[a-z0-9-]{0,61}[a-z0-9])?\.)*[a-z0-9](?:[a-z0-9-]{0,61}[a-z0-9])?|\[(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\])$/i).test(element.get('value'));
*/
for (;;) {
$this->output .= $this->a;
$this->a = $this->get();
if ($this->a === ']') {
break;
} elseif ($this->a === '\\') {
$this->output .= $this->a;
$this->a = $this->get();
} elseif (ord($this->a) <= self::ORD_LF) {
throw new JSMinException('Unterminated regular expression set in regex literal.');
}
}
} elseif ($this->a === '/') {
break;
} elseif ($this->a === '\\') {
$this->output .= $this->a;
$this->a = $this->get();
} elseif (ord($this->a) <= self::ORD_LF) {
throw new JSMinException('Unterminated regular expression literal.');
}
$this->output .= $this->a;
}
$this->b = $this->next();
}
}
}
/**
* Get next char. Convert ctrl char to space.
*
* @return string|null
*/
protected function get() {
$c = $this->lookAhead;
$this->lookAhead = null;
if ($c === null) {
if ($this->inputIndex < $this->inputLength) {
$c = substr($this->input, $this->inputIndex, 1);
$this->inputIndex += 1;
} else {
$c = null;
}
}
if ($c === "\r") {
return "\n";
}
if ($c === null || $c === "\n" || ord($c) >= self::ORD_SPACE) {
return $c;
}
return ' ';
}
/**
* Is $c a letter, digit, underscore, dollar sign, or non-ASCII character.
*
* @return bool
*/
protected function isAlphaNum($c) {
return ord($c) > 126 || $c === '\\' || preg_match('/^[\w\$]$/', $c) === 1;
}
/**
* Perform minification, return result
*
* @uses action()
* @uses isAlphaNum()
* @uses get()
* @uses peek()
* @return string
*/
protected function min() {
if (0 == strncmp($this->peek(), "\xef", 1)) {
$this->get();
$this->get();
$this->get();
}
$this->a = "\n";
$this->action(self::ACTION_DELETE_A_B);
while ($this->a !== null) {
switch ($this->a) {
case ' ':
if ($this->isAlphaNum($this->b)) {
$this->action(self::ACTION_KEEP_A);
} else {
$this->action(self::ACTION_DELETE_A);
}
break;
case "\n":
switch ($this->b) {
case '{':
case '[':
case '(':
case '+':
case '-':
case '!':
case '~':
$this->action(self::ACTION_KEEP_A);
break;
case ' ':
$this->action(self::ACTION_DELETE_A_B);
break;
default:
if ($this->isAlphaNum($this->b)) {
$this->action(self::ACTION_KEEP_A);
}
else {
$this->action(self::ACTION_DELETE_A);
}
}
break;
default:
switch ($this->b) {
case ' ':
if ($this->isAlphaNum($this->a)) {
$this->action(self::ACTION_KEEP_A);
break;
}
$this->action(self::ACTION_DELETE_A_B);
break;
case "\n":
switch ($this->a) {
case '}':
case ']':
case ')':
case '+':
case '-':
case '"':
case "'":
$this->action(self::ACTION_KEEP_A);
break;
default:
if ($this->isAlphaNum($this->a)) {
$this->action(self::ACTION_KEEP_A);
}
else {
$this->action(self::ACTION_DELETE_A_B);
}
}
break;
default:
$this->action(self::ACTION_KEEP_A);
break;
}
}
}
return $this->output;
}
/**
* Get the next character, skipping over comments. peek() is used to see
* if a '/' is followed by a '/' or '*'.
*
* @uses get()
* @uses peek()
* @throws JSMinException On unterminated comment.
* @return string
*/
protected function next() {
$c = $this->get();
if ($c === '/') {
switch($this->peek()) {
case '/':
for (;;) {
$c = $this->get();
if (ord($c) <= self::ORD_LF) {
return $c;
}
}
case '*':
$this->get();
for (;;) {
switch($this->get()) {
case '*':
if ($this->peek() === '/') {
$this->get();
return ' ';
}
break;
case null:
throw new JSMinException('Unterminated comment.');
}
}
default:
return $c;
}
}
return $c;
}
/**
* Get next char. If is ctrl character, translate to a space or newline.
*
* @uses get()
* @return string|null
*/
protected function peek() {
$this->lookAhead = $this->get();
return $this->lookAhead;
}
}
// -- Exceptions ---------------------------------------------------------------
class JSMinException extends Exception {}
?>总结：以上就是本篇文的全部内容，希望能对大家的学习有所帮助。
相关推荐：
Atas ialah kandungan terperinci php实现压缩合并js的方法. Untuk maklumat lanjut, sila ikut artikel berkaitan lain di laman web China PHP!
![[Web front-end] Permulaan pantas Node.js](https://img.php.cn/upload/course/000/000/067/662b5d34ba7c0227.png)
