php remove non alphanumeric characters

The following is about the small series for everyone to collect and organize the regular expression of PHP, the specific content please see below detailed $str = Preg_replace ("/() (. *?) ()/", ' \1\2\3 ', $str); It uses three sub

This article is excerpted from: php functions implementation principles and performance analysis. functions are one of the most basic technical units in any language. What are the features of php functions? How is function call implemented? What is

PHP code $STR = Preg_replace ("/() (. *?) ()/", ' \1\2\3", $str); The uses three sub modes (one in each parenthesis), the first one is the link start tag, the second is the link text, and the third is then \1, \2, and \3 in the second argument,

Regular expressions for string processing, form verification, and other occasions, practical and efficient. This article collects some common expressions: $str = Preg_replace ("/( ) (. *?) ()/", ' \1\2\3 ', $str); It uses three sub

HDK (Baidu)ObjectiveIn any language, a function is the most basic constituent unit. What are the features of PHP functions? How is a function call implemented? What is the performance of PHP functions and what are the suggestions for using them?

ObjectiveIn any language, a function is the most basic constituent unit. What are the features of PHP functions? How is a function call implemented? What is the performance of PHP functions and what are the suggestions for using them?This paper will

First, Let's take a look at two special characters: ' ^ ' and ' $ ' they are used to match the start and end of the string, respectively, to illustrate "^the": matches a string that starts with "the";"Of despair$": matches a string ending with "of

Author: HDK (Baidu) Preface In any language, a function is the most basic component unit. What are the features of php functions? How is function calling implemented? What is the performance of php functions? What are the suggestions for use? This

Original author: a.m. kuchling (amk@amk.ca) Licensing: Authoring Sharing protocol Translation staff: Firehare Proofreading Staff: Leal Applicable version: Python 1.5 and subsequent versions http://wiki.ubuntu.org.cn/Python%E6%AD%A3%E5%88%99%E8%A1%A8%

Chinese code Double-byte character encoding range: 1. GBK (gb2312/gb18030) \X00-\XFF→GBK two-byte coding range\x20-\x7f→ascii remove characters from non-Chinese characters\xa1-\xff Chinese →gb2312 out all Chinese (excluding alphanumeric and