运用PHP函数parse_url分析信息抓取

1. $url = "http://www.electrictoolbox.
   com/php-extract-domain-from-full-url/";  
2. $parts = parse_url($url); 

输出:

1. Array  
2. (  
3. [scheme] => http  
4. [host] => www.electrictoolbox.com  
5. [path] => /php-extract-
   domain-from-full-url/  
6. )  

又如PHP函数parse_url使用方法: 

<ol class="dp-xml">
<li class="alt"><span><span class="tag"><span> ?php  </span></span></span></li>
<li>
<span>$</span><span class="attribute">url</span><span> = </span><span class="attribute-value">'http://username:password<br>@hostname/path?arg=value#anchor'</span><span>;  </span>
</li>
<li class="alt"><span>print_r(parse_url($url));  </span></li>
<li><span>echo parse_url($url, PHP_URL_PATH);  </span></li>
<li class="alt">
<span class="tag">?></span><span> </span>
</li>
</ol>

输出:

<ol class="dp-xml">
<li class="alt"><span><span>Array  </span></span></li>
<li><span>(  </span></li>
<li class="alt">
<span>[scheme] =</span><span class="tag">></span><span> http  </span>
</li>
<li>
<span>[host] =</span><span class="tag">></span><span> hostname  </span>
</li>
<li class="alt">
<span>[user] =</span><span class="tag">></span><span> username  </span>
</li>
<li>
<span>[pass] =</span><span class="tag">></span><span> password  </span>
</li>
<li class="alt">
<span>[path] =</span><span class="tag">></span><span> /path  </span>
</li>
<li>
<span>[query] =</span><span class="tag">></span><span> </span><span class="attribute">arg</span><span>=</span><span class="attribute-value">value</span><span> </span>
</li>
<li class="alt">
<span>[fragment] =</span><span class="tag">></span><span> anchor  </span>
</li>
<li><span>)  </span></li>
</ol>

可以看到,PHP函数parse_url可以很容易分解出一个URL的各个部,那如果要拿指定的部分出来的话也很容易,如

echo parse_url($url, PHP_URL_PATH);就是在第二个参数中,设定如下的参数:

PHP_URL_SCHEME, PHP_URL_HOST, PHP_URL_PORT, PHP_URL_USER, PHP_URL_PASS, PHP_URL_PATH, PHP_URL_QUERY or PHP_URL_FRAGMENT.