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

Example #1 str_repeat() 范例


<?php
echo str_repeat("-=", 10);
?>

以上例程会输出：

-=-=-=-=-=-=-=-=-=-=

参见

for
str_pad() - 使用另一个字符串填充字符串为指定长度
substr_count() - 计算字串出现的次数

User Contributed Notes

Alexander Ovsiyenko 29-Jun-2018 11:22


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

Anonymous 23-Oct-2011 04:51


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 ...

Damien Bezborodov 28-Apr-2009 12:45


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

?,?,?

claude dot pache at gmail dot com 10-Feb-2009 02:25


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;

}

?>

21-Jul-2003 10:45


str_repeat does not repeat symbol with code 0 on some (maybe all?) systems (tested on PHP Version 4.3.2 , FreeBSD 4.8-STABLE i386 ).



Use <pre>

while(strlen($str) < $desired) $str .= chr(0);

</pre> to have string filled with zero-symbols.