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
The above is the detailed content of Summary of string manipulation functions in php. For more information, please follow other related articles on the PHP Chinese website!

PHPsessionstrackuserdataacrossmultiplepagerequestsusingauniqueIDstoredinacookie.Here'showtomanagethemeffectively:1)Startasessionwithsession_start()andstoredatain$_SESSION.2)RegeneratethesessionIDafterloginwithsession_regenerate_id(true)topreventsessi

In PHP, iterating through session data can be achieved through the following steps: 1. Start the session using session_start(). 2. Iterate through foreach loop through all key-value pairs in the $_SESSION array. 3. When processing complex data structures, use is_array() or is_object() functions and use print_r() to output detailed information. 4. When optimizing traversal, paging can be used to avoid processing large amounts of data at one time. This will help you manage and use PHP session data more efficiently in your actual project.

The session realizes user authentication through the server-side state management mechanism. 1) Session creation and generation of unique IDs, 2) IDs are passed through cookies, 3) Server stores and accesses session data through IDs, 4) User authentication and status management are realized, improving application security and user experience.

Tostoreauser'snameinaPHPsession,startthesessionwithsession_start(),thenassignthenameto$_SESSION['username'].1)Usesession_start()toinitializethesession.2)Assigntheuser'snameto$_SESSION['username'].Thisallowsyoutoaccessthenameacrossmultiplepages,enhanc

Reasons for PHPSession failure include configuration errors, cookie issues, and session expiration. 1. Configuration error: Check and set the correct session.save_path. 2.Cookie problem: Make sure the cookie is set correctly. 3.Session expires: Adjust session.gc_maxlifetime value to extend session time.

Methods to debug session problems in PHP include: 1. Check whether the session is started correctly; 2. Verify the delivery of the session ID; 3. Check the storage and reading of session data; 4. Check the server configuration. By outputting session ID and data, viewing session file content, etc., you can effectively diagnose and solve session-related problems.

Multiple calls to session_start() will result in warning messages and possible data overwrites. 1) PHP will issue a warning, prompting that the session has been started. 2) It may cause unexpected overwriting of session data. 3) Use session_status() to check the session status to avoid repeated calls.

Configuring the session lifecycle in PHP can be achieved by setting session.gc_maxlifetime and session.cookie_lifetime. 1) session.gc_maxlifetime controls the survival time of server-side session data, 2) session.cookie_lifetime controls the life cycle of client cookies. When set to 0, the cookie expires when the browser is closed.


Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Hot Tools

SAP NetWeaver Server Adapter for Eclipse
Integrate Eclipse with SAP NetWeaver application server.

Atom editor mac version download
The most popular open source editor

EditPlus Chinese cracked version
Small size, syntax highlighting, does not support code prompt function

SublimeText3 English version
Recommended: Win version, supports code prompts!

MantisBT
Mantis is an easy-to-deploy web-based defect tracking tool designed to aid in product defect tracking. It requires PHP, MySQL and a web server. Check out our demo and hosting services.
