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HomeBackend DevelopmentPHP TutorialSummary of string manipulation functions in php

Summary of string manipulation functions in php

Aug 22, 2017 am 09:13 AM
phpstringSummarize

The following editor will bring you a collection of string operation functions based on PHP. The editor thinks it’s pretty good, so I’ll share it with you now and give it as a reference. Let’s follow the editor and take a look.

1. Find character position function:


strpos($str,search,[int])://查找search在$str中的第一次位置从int开始;
strrpos($str,search,[int])://查找search在$str中的最后一次出现的位置从int开始

2. Extract sub-character function (double bytes)


submit($str,int start[,int length])://从$str中strat位置开始提取[length长度的字符串]。
strstr($str1,$str2)://从$str1(第一个的位置)搜索$str2并从它开始截取到结束字符串;若没有则返回FALSE。
stristr()//功能同strstr,只是不区分大小写。
strrchr()//从最后一次搜索到的字符处返回;用处:取路径中文件名

3. Replace string


str_replace(search,replace,$str):从$str中查找search用replace来替换
str_irreplace(search,replace,$str):
strtr($str,search,replace):这个函数中replace不能为"";
substr_replace($Str,$rep,$start[,length])$str原始字符串,$rep替换后的新字符串,$start起始位置,$length替换的长度,该项可选

4. Query string length


int strlen($str)

5. Comparison character function

int strcmp($str1,$str2):$str1>=

6. Split into array function

str_split($str,len): Split $str according to the length of len and return the array split(search,$str[, int]): Split $str according to the search character to return the array int. How many times will it be split? The following will not be split explode(search,$str[,int])

##7, Remove spaces:

ltrim, rtrim, trim

##8, add spaces functionchunk_split ($str,2); Press 2 characters into the $str character to add a space;

9. Return the specified character or ascii chr、ord


10. HTML code related functionsnl2br(): Convert \n to .strip_tags($str[,'

']): //Remove HTML and PHP tags htmlspecialchars($str[,parameter])://The normal output of the page is the conversion method of HTML code parameters

11. Character case conversion function strtolower($str) Convert the string to lowercase strtoupper($str) Convert the string to uppercase ucfirst($ str) Convert the first character of the function to uppercase ucwords($str) Convert the first letter of each word to uppercase

12. Database related functions addslashes($str): Convert single quotes ('), double quotes ("), backslashes (\) and NUL strings in str to \',\",\\. magic_quotes_gpc = On automatically escapes the content of the get post cookie get_magic_quotes_gpc() detects whether magic_quotes_gpcstripslashes() is turned on and removes backslashes in the string

13. Connection functionimplode(str,$arr) concatenates the string array into a string according to the specified characters; the implode() function has an alias function join

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