rtrim
(PHP 4, PHP 5)
rtrim — Strip whitespace (or other characters) from the end of a string
说明
string rtrim
( string $str
[, string $charlist
] )
This function returns a string with whitespace stripped from the end of str .
Without the second parameter, rtrim() will strip these characters:
- " " (ASCII 32 (0x20)), an ordinary space.
- "\t" (ASCII 9 (0x09)), a tab.
- "\n" (ASCII 10 (0x0A)), a new line (line feed).
- "\r" (ASCII 13 (0x0D)), a carriage return.
- "\0" (ASCII 0 (0x00)), the NUL-byte.
- "\x0B" (ASCII 11 (0x0B)), a vertical tab.
参数
- str
-
The input string.
- charlist
-
You can also specify the characters you want to strip, by means of the charlist parameter. Simply list all characters that you want to be stripped. With .. you can specify a range of characters.
返回值
Returns the modified string.
更新日志
| 版本 | 说明 |
|---|---|
| 4.1.0 | The charlist parameter was added. |
范例
Example#1 Usage example of rtrim()
<?php
$text = "\t\tThese are a few words :) ... ";
$binary = "\x09Example string\x0A";
$hello = "Hello World";
var_dump($text, $binary, $hello);
print "\n";
$trimmed = rtrim($text);
var_dump($trimmed);
$trimmed = rtrim($text, " \t.");
var_dump($trimmed);
$trimmed = rtrim($hello, "Hdle");
var_dump($trimmed);
// trim the ASCII control characters at the end of $binary
// (from 0 to 31 inclusive)
$clean = rtrim($binary, "\x00..\x1F");
var_dump($clean);
?>
上例将输出：
string(32) " These are a few words :) ... " string(16) " Example string " string(11) "Hello World" string(30) " These are a few words :) ..." string(26) " These are a few words :)" string(9) "Hello Wor" string(15) " Example string"
