CURL application in PHP and based on modified Google implementation

能做什么

<code>PHP中的curl库最基本的用途就是去简单有效地*抓取网页的内容*，然后利用抓取到的网页数据经程序的方式进行处理和分析，最终得到你所想要的数据。当然了，这是最基本的用法，还有其他复杂有趣的用途，这取决于你的curl_setopt()行数的设置
</code>

怎么用

<code>首先，你的PHP中必须安装有curl的扩展插件，即phpinfo中有如下显示

![这里写图片描述](http://img.blog.csdn.net/20150309200749680)

然后就可以开始使用了，具体步骤：

 1.用curl_init()初始化一个curl会话
 2.通过curl_setopt()来设置需要的全部选项
 3.用curl_exec()来执行会话
 4.执行完后使用curl_close()关闭会话
</code>

ps:curl_setopt()是curl使用的关键，很多复杂的用法都是基于此

一个简单的例子

<code><?php
<span>//初始化一个curl对象</span><span>$curl</span>=curl_init(<span>"http://www.baidu.com"</span>);

<span>//将抓取的数据已文本的形式保存</span><span>$fp</span>=<span>fopen</span>(<span>"test.txt"</span>);

<span>//设置curl_setopt()参数</span>
curl_setopt(<span>$ch</span>,CURLOPT_FILE,<span>$fp</span>);
curl_setopt(<span>$ch</span>,CURLOPT_HEADER,<span>0</span>);

<span>//执行curl_exec();</span>
curl_exec(<span>$ch</span>);

<span>//关闭curl会话</span>
curl_exec(<span>$ch</span>);
curl_close(<span>$ch</span>);
<span>fclose</span>(<span>$fp</span>);</code>

以上例子来自官方文档

利用CURL实现抓取GOOGLE的host脚本

<code><?php
<span>//初始化curl对话</span><span>$curl</span>=curl_init();

<span>//设置curl_setopt</span>
curl_setopt(<span>$curl</span>, CURLOPT_URL, <span>'http://www.360kb.com/kb/2_122.html'</span>);
curl_setopt(<span>$curl</span>,CURLOPT_HEADER,<span>0</span>);
curl_setopt(<span>$curl</span>, CURLOPT_RETURNTRANSFER, true);

<span>//执行curl</span><span>$data</span>=curl_exec(<span>$curl</span>);

<span>//关闭curl资源</span>
curl_close(<span>$curl</span>);


<span>//清楚HTML标签</span><span>$data</span>=strip_tags(<span>$data</span>);
<span>//处理的读入数据</span><span>$data</span>=substr(<span>$data</span>, strpos(<span>$data</span>, <span>'#google hosts'</span>));
<span>$data</span>=substr(<span>$data</span>,<span>0</span>,strpos(<span>$data</span>, <span>'#google hosts 2015 end'</span>));
<span>$data</span>=str_replace(<span>' '</span>, <span>'  '</span>, <span>$data</span>);

<span>//写入host</span><span>$host</span>=file_get_contents(<span>"C:\\Windows\\System32\\drivers\\etc\\HOSTS"</span>);
<span>$host</span>=substr(<span>$host</span>,<span>0</span>,strpos(<span>$host</span>, <span>'#google hosts'</span>));
<span>$host</span>.=<span>$data</span>;
<span>$fh</span>=<span>fopen</span>(<span>"C:\\Windows\\System32\\drivers\\etc\\HOSTS"</span>, <span>'w'</span>);
<span>fwrite</span>(<span>fopen</span>(<span>"C:\\Windows\\System32\\drivers\\etc\\HOSTS"</span>, <span>'w'</span>), <span>$host</span>);
<span>fclose</span>(<span>$fh</span>);
</code>

以上就介绍了PHP中CURL应用与基于的修改Google实现，包括了方面的内容，希望对PHP教程有兴趣的朋友有所帮助。