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HomeBackend DevelopmentPHP TutorialSome common string functions in PHP

Some common string functions in PHP

Apr 03, 2018 pm 01:48 PM
phpstringCommonly used

本篇文章介绍的是php中的一些常用字符串函数,在这里分享给大家,也可以给有需要的朋友一点参考,大家一起来看看吧

1、获取字符串长度 strlen()


2、删除空白字符串 trim(), ltrim(), rtrim() 分别用来删除 字符串首尾,字符串开头,字符串结尾的空白符。

trim(),ltrim(),rtrim()函数默认删除的字符:

符号 ASCII码 意义
“ ” 0x20 空格
“\t” 0x09 制表符
"\n" 0X0A 换行符
"\r" 0x0D 回车符
"\0" 0x00 空字符
"\x0B" 0x0B 纵向制表符


//examgle
$title = "  Programming PHP  \n";
$str1 = ltrim($title);//Promgromming PHP \n
$str2 = rtrim($title);//  Programming PHP
$str3 = trim($title);//Programming PHP
//可以使用带参数的trim()函数来删除开头或结尾的空白而不删除制表符
$record = " Fred\tFlintstone\t35\tWilma\t  \n";
$record = trim($record, " \r\n\0\x0B");
//此时record 值为:"Fred\tFlintstone\t35\tWilma\t"

改变大小写

strtolower(),strtoupper() 操作整个字符串

ucfirst()仅操作字符串的第一个字符,ucwords()操作字符串中每个单词的第一个字符

//example
$str1 = "FRED fintstone";
$str2 = "barney rubble" ;
print(strtolower($str1));
print(strtoupper($str1));
print(ucfirst($str2));
print(ucwords($str2));
//输出
fred fintstone
FRED FINTSTONE
Barney rubble
Barney Rubble

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php 字符串函数总结

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