php has two functions to find the length of a string: 1. The strlen() function can calculate the length of an English string, and the syntax is "strlen($string)"; 2. The mb_strlen() function can By setting the character encoding, calculate the length of an English string, a Chinese string, or a mixed Chinese-English string. The syntax is "mb_strlen($string,"Character encoding")".
The operating environment of this tutorial: Windows 7 system, PHP version 8.1, DELL G3 computer
Commonly used in PHP to calculate the length of a string There are two functions, namely strlen() and mb_strlen() functions. When processing all-English strings, the effects of these two functions are the same. However, when processing mixed Chinese and English strings or pure Chinese strings, these two functions will have some differences:
- # The ##strlen() function can calculate the length of English strings, but for mixed Chinese and English or pure Chinese strings, the length cannot be accurately calculated.
- mb_strlen() function can calculate the length of English strings, Chinese strings or mixed Chinese and English strings.
1. strlen() function finds the length of a string
strlen() function can return the length of a given string, its syntax format As follows:strlen($string)
- The parameter $string is the string whose length needs to be calculated. Returns 0 if $string is empty.
Note: In the strlen() function, numbers, English, decimal point, underline and space occupy one character; while a GB2312 encoded Chinese character occupies two characters. A UTF-8 encoded Chinese character is three characters long.Example:
<?php header("Content-type:text/html;charset=utf-8"); $str = "hello world!"; echo '字符串 “'.$str.'” 的长度为:'.strlen($str).'<br>'; ?>$str string contains 10 English letters, 1 space and 1 English exclamation mark, a total of 12 characters, so the output length is 12.
<?php header("Content-type:text/html;charset=utf-8"); $str = "hello 你好!"; echo '字符串 “'.$str.'” 的长度为:'.strlen($str).'<br>'; ?>
2. mb_strlen() function finds the length of a string
mb_strlen() function can also return the length of a string. The syntax format is as follows:mb_strlen($str [, $encoding = mb_internal_encoding()])
- $str is the string whose length needs to be calculated
- $encoding is an optional parameter, which is the character encoding. If If omitted, the internal character encoding is used.
Note: Unlike the strlen() function, in the mb_strlen() function, whether it is Chinese characters, English, numbers, decimal points, underscores and spaces, they only occupy one character in length.[Example] Use the mb_strlen() function to get the string length.
<?php header("Content-type:text/html;charset=utf-8"); $str = "hello 你好!"; echo '字符串 “'.$str.'” 的长度为:'.mb_strlen($str,"utf-8").'<br>'; $str = "欢迎来到PHP中文网!"; echo '<br>字符串 “'.$str.'” 的长度为:'.mb_strlen($str,'utf-8').'<br>'; ?>
$encoding parameters.
PHP Video Tutorial"
The above is the detailed content of What is the function in php to find the length of a string?. For more information, please follow other related articles on the PHP Chinese website!

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

Zend Studio 13.0.1
Powerful PHP integrated development environment

WebStorm Mac version
Useful JavaScript development tools

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

Safe Exam Browser
Safe Exam Browser is a secure browser environment for taking online exams securely. This software turns any computer into a secure workstation. It controls access to any utility and prevents students from using unauthorized resources.

mPDF
mPDF is a PHP library that can generate PDF files from UTF-8 encoded HTML. The original author, Ian Back, wrote mPDF to output PDF files "on the fly" from his website and handle different languages. It is slower than original scripts like HTML2FPDF and produces larger files when using Unicode fonts, but supports CSS styles etc. and has a lot of enhancements. Supports almost all languages, including RTL (Arabic and Hebrew) and CJK (Chinese, Japanese and Korean). Supports nested block-level elements (such as P, DIV),
