(PHP 4, PHP 5, PHP 7, PHP 8)
trim — Strip whitespace (or other characters) from the beginning and end of a string
This function returns a string with whitespace stripped from the
beginning and end of string
.
Without the second parameter,
trim() will strip these characters:
" "
: символ ASCII
SP 0x20
, звичайний пропуск.
"\t"
: символ ASCII
HT 0x09
, табуляція.
"\n"
: символ ASCII
LF 0x0A
, новий рядок.
"\r"
: символ ASCII
CR 0x0D
, повернення каретки.
"\0"
: символ ASCII
NUL 0x00
, NUL-байт.
"\v"
: символ ASCII
VT 0x0B
, вертикальна табуляція.
string
The string that will be trimmed.
characters
characters
. Необхідно просто записати туди
усі непотрібні символи. За допомогою ..
можна задати
діапазон символів за зростанням.
The trimmed string.
Приклад #1 Usage example of trim()
<?php
$text = "\t\tThese are a few words :) ... ";
$binary = "\x09Example string\x0A";
$hello = "Hello World";
var_dump($text, $binary, $hello);
print "\n";
$trimmed = trim($text);
var_dump($trimmed);
$trimmed = trim($text, " \t.");
var_dump($trimmed);
$trimmed = trim($hello, "Hdle");
var_dump($trimmed);
$trimmed = trim($hello, 'HdWr');
var_dump($trimmed);
// trim the ASCII control characters at the beginning and end of $binary
// (from 0 to 31 inclusive)
$clean = trim($binary, "\x00..\x1F");
var_dump($clean);
?>
Поданий вище приклад виведе:
string(32) " These are a few words :) ... " string(16) " Example string " string(11) "Hello World" string(28) "These are a few words :) ..." string(24) "These are a few words :)" string(5) "o Wor" string(9) "ello Worl" string(14) "Example string"
Приклад #2 Trimming array values with trim()
<?php
function trim_value(&$value)
{
$value = trim($value);
}
$fruit = array('apple','banana ', ' cranberry ');
var_dump($fruit);
array_walk($fruit, 'trim_value');
var_dump($fruit);
?>
Поданий вище приклад виведе:
array(3) { [0]=> string(5) "apple" [1]=> string(7) "banana " [2]=> string(11) " cranberry " } array(3) { [0]=> string(5) "apple" [1]=> string(6) "banana" [2]=> string(9) "cranberry" }
Зауваження: Possible gotcha: removing middle characters
Because trim() trims characters from the beginning and end of a string, it may be confusing when characters are (or are not) removed from the middle.
trim('abc', 'bad')
removes both 'a' and 'b' because it trims 'a' thus moving 'b' to the beginning to also be trimmed. So, this is why it "works" whereastrim('abc', 'b')
seemingly does not.