str_repeat
(PHP 4, PHP 5, PHP 7, PHP 8)
str_repeat — 重复一个字符串
说明
str_repeat(string
$input, int $multiplier): string
返回 input 重复
multiplier 次后的结果。
参数
-
input -
待操作的字符串。
-
multiplier -
input被重复的次数。multiplier必须大于等于 0。如果multiplier被设置为 0，函数返回空字符串。
返回值
返回重复后的字符串。
范例
示例 #1 str_repeat() 范例
<?php
echo str_repeat("-=", 10);
?>
以上例程会输出：
-=-=-=-=-=-=-=-=-=-=
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User Contributed Notes 5 notes
Damien Bezborodov ¶
13 years ago
Here is a simple one liner to repeat a string multiple times with a separator:
<?php
implode($separator, array_fill(0, $multiplier, $input));
?>
Example script:
<?php
// How I like to repeat a string using standard PHP functions
$input = 'bar';
$multiplier = 5;
$separator = ',';
print implode($separator, array_fill(0, $multiplier, $input));
print "\n";
// Say, this comes in handy with count() on an array that we want to use in an
// SQL query such as 'WHERE foo IN (...)'
$args = array('1', '2', '3');
print implode(',', array_fill(0, count($args), '?'));
print "\n";
?>
Example Output:
bar,bar,bar,bar,bar
?,?,?
Anonymous ¶
10 years ago
hi guys ,
i've faced this example :
<?php
$my_head = str_repeat("°~", 35);
echo $my_head;
?>
so , the length should be 35x2 = 70 !!!
if we echo it :
<?php
$my_head = str_repeat("°~", 35);
echo strlen($my_head); // 105
echo mb_strlen($my_head, 'UTF-8'); // 70
?>
be carefull with characters and try to use mb_* package to make sure everything goes well ...
claude dot pache at gmail dot com ¶
13 years ago
Here is a shorter version of Kees van Dieren's function below, which is moreover compatible with the syntax of str_repeat:
<?php
function str_repeat_extended($input, $multiplier, $separator='')
{
return $multiplier==0 ? '' : str_repeat($input.$separator, $multiplier-1).$input;
}
?>
Alexander Ovsiyenko ¶
3 years ago
http://php.net/manual/en/function.str-repeat.php#90555
Damien Bezborodov , yeah but execution time of your solution is 3-5 times worse than str_replace.
<?php
function spam($number) {
return str_repeat('test', $number);
}
function spam2($number) {
return implode('', array_fill(0, $number, 'test'));
}
//echo spam(4);
$before = microtime(true);
for ($i = 0; $i < 100000; $i++) {
spam(10);
}
echo microtime(true) - $before , "\n"; // 0.010297
$before = microtime(true);
for ($i = 0; $i < 100000; $i++) {
spam2(10);
}
echo microtime(true) - $before; // 0.032104