trim
trim — 去除字符串首尾处的空白字符(或者其他字符)
说明
string trim ( string $str [, string $charlist = " \t\n\r\0\x0B" ] )
此函数返回字符串 str 去除首尾空白字符后的结果。如果不指定第二个参数, trim() 将去除这些字符:
1. " " (ASCII 32 (0x20)),普通空格符。
2. "\t" (ASCII 9 (0x09)),制表符。
3. "\n" (ASCII 10 (0x0A)),换行符。
4. "\r" (ASCII 13 (0x0D)),回车符。
5. "\0" (ASCII 0 (0x00)),空字节符。
6. "\x0B" (ASCII 11 (0x0B)),垂直制表符。
- <?php
- $text = "\t\tThese are a few words ) ... " ;
- $binary = "\x09Example string\x0A" ;
- $hello = "Hello World" ;
- $trimmed = trim ( $text );
- var_dump ( $trimmed );//string(28) "These are a few words ) ..."
- $trimmed = trim ( $text , " \t." );
- var_dump ( $trimmed );//string(24) "These are a few words )"
- $trimmed = trim ( $hello , "Hdle" );
- var_dump ( $trimmed );//string(5) "o Wor"
- // 清除 $binary 首位的 ASCII 控制字符
- // (包括 0-31)
- $clean = trim ( $binary , "\x00..\x1F" );
- var_dump ( $clean );//string(14) "Example string"
ltrim
ltrim — 删除字符串开头的空白字符(或其他字符)用法同上;
说明
string ltrim ( string $str [, string $character_mask ] )
删除字符串开头的空白字符(或其他字符)
rtrim
rtrim — 删除字符串末端的空白字符(或者其他字符)用法同上;
说明
string rtrim ( string $str [, string $character_mask ] )
该函数删除 str 末端的空白字符并返回。