php 获取页面中的指定内容类

功能：

1.获取内容中的url，email，image。

2.替换内容中的url，email，image。

url：<a href="url">xxx</a>

email：admin@admin.com

image：<img src="image">

Grep.class.php

<?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" => "/<a.*?href="((http(s)?://).*?)".*?/si",
                            "email" => "/([w-.]+@[w-.]+(.w+))/",
                            "image" => "/<img.*?src="(http://.+.(jpg|jpeg|gif|bmp|png))">/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

<?php
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]" : "";
}
?>