本文为大家下使用php如何获取页面中的指定内容，而且以封装成类，需要的朋友可以参考下本文

功能：

1.获取内容中的url，email，image。

2.替换内容中的url，email，image。

url：xxx

email：admin@admin.com

image：

Grep.class.php

/** grep class

* Date: 2013-06-15

* Author: fdipzone

* Ver: 1.0

*

* Func:

*

* set: 设置内容

* get: 返回指定的内容

* replace: 返回替换后的内容

* get_pattern 根据type返回pattern

*/

class Grep{ // class start

private $_pattern = array(

'url' => '/

'email' => '/([\w\-\.]+@[\w\-\.]+(\.\w+))/',

'image' => '//i'

);

private $_content = ''; // 源内容

/* 設置搜尋的內容

* @param String $content

*/

public function set($content=''){

$this->_content = $content;

}

/* 获取指定内容

* @param String $type

* @param int $unique 0:all 1:unique

* @return Array

*/

public function get($type='', $unique=0){

$type = strtolower($type);

if($this->_content=='' || !in_array($type, array_keys($this->_pattern))){

return array();

}

$pattern = $this->get_pattern($type); // 获取pattern

preg_match_all($pattern, $this->_content, $matches);

return isset($matches[1])? ( $unique==0? $matches[1] : array_unique($matches[1]) ) : array();

}

/* 获取替换后的内容

* @param String $type

* @param String $callback

* @return String

*/

public function replace($type='', $callback=''){

$type = strtolower($type);

if($this->_content=='' || !in_array($type, array_keys($this->_pattern)) || $callback==''){

return $this->_content;

}

$pattern = $this->get_pattern($type);

return preg_replace_callback($pattern, $callback, $this->_content);

}

/* 根据type获取pattern

* @param String $type

* @return String

*/

private function get_pattern($type){

return $this->_pattern[$type];

}

} // class end

?>

Demo

header('content-type:text/htm;charset=utf8');

require('Grep.class.php');

$content = file_get_contents('http://www.test.com/');

$obj = new Grep();

$obj->set($content);

$url = $obj->get('url', 0);

$email = $obj->get('email', 1);

$image = $obj->get('image', 1);

print_r($url);

print_r($email);

print_r($image);

$url_new = $obj->replace('url', 'replace_url');

echo $url_new;

function replace_url($matches){

return isset($matches[1])? '[url]'.$matches[1].'[/url]' : '';

}

?>