Webbots, Spiders, and Screen Scrapers, 2nd Edition

Useful PHP Functions

In addition to the parsing functions included in LIB_parse, described earlier, PHP contains a multitude of built-in parsing functions. The following is a brief sample of the most valuable built-in PHP parsing functions, along with examples of how they are used.

Detecting Whether a String Is Within Another String

You can use the stristr() function to tell your webbot whether or not a string contains another string. The PHP community commonly uses the term haystack to refer to the entire unparsed text and the term needle to refer to the substring within the larger string. The function stristr() looks for an occurrence of needle in haystack. If found, stristr() returns a substring of haystack from the occurrence of needle to the ...