ltrim
(PHP 4, PHP 5)
ltrim — Strip whitespace (or other characters) from the beginning of a string
Beskrivelse
string ltrim
( string $str
[, string $charlist
] )
Strip whitespace (or other characters) from the beginning of a string.
Parameterliste
- 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.
Returneringsværdier
This function returns a string with whitespace stripped from the beginning of str . Without the second parameter, ltrim() 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.
ChangeLog
Version | Beskrivelse |
---|---|
4.1.0 | The charlist parameter was added. |
Eksempler
Example#1 Usage example of ltrim()
<?php
$text = "\t\tThese are a few words :) ... ";
$binary = "\x09Example string\x0A";
$hello = "Hello World";
var_dump($text, $binary, $hello);
print "\n";
$trimmed = ltrim($text);
var_dump($trimmed);
$trimmed = ltrim($text, " \t.");
var_dump($trimmed);
$trimmed = ltrim($hello, "Hdle");
var_dump($trimmed);
// trim the ASCII control characters at the beginning of $binary
// (from 0 to 31 inclusive)
$clean = ltrim($binary, "\x00..\x1F");
var_dump($clean);
?>
Ovenstående eksempel vil udskrive:
string(32) " These are a few words :) ... " string(16) " Example string " string(11) "Hello World" string(30) "These are a few words :) ... " string(30) "These are a few words :) ... " string(7) "o World" string(15) "Example string "