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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