概述
爬虫是我们在做程序时经常会遇到的一种功能。PHP有许多开源的爬虫工具,如snoopy,这些开源的爬虫工具,通常能帮我们完成大部分功能,但是在某种情况下,我们需要自己实现一个爬虫,本篇文章对PHP实现爬虫的方式做个总结。
PHP实现爬虫主要方法
1.file()函数
2.file_get_contents()函数
3.fopen()->fread()->fclose()方式
4.curl方式
5.fsockopen()函数,socket方式
6.使用开源工具,如:snoopy
PHP解析XML或HTML主要方式
1.正则表达式
2.PHP DOMDocument对象
3.插件,如:PHP Simple HTML DOM Parser
总结
这里对PHP实现爬虫的方式做个简单得总结,本篇设计到得内容还有很多,稍后会对PHP解析HTML和XML的方式做个总结。

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