(PHP 4, PHP 5, PHP 7, PHP 8)
array_pad — Pad array to the specified length with a value
Description
array_pad(array $array, int $length,
mixed $value): array
Parameters
array Initial array of values to pad.
length New size of the array.
value Value to pad if array is less than length.
Return Values
Returns a copy of the array padded to size specified by length with value value. If length is positive then the array is padded on the right, if it's negative then on the left. If the absolute value of length is less than or equal to the length of the array then no padding takes place.
Examples
Example #1
array_pad() example
<?php
$input = array(12, 10, 9);$result = array_pad($input, 5, 0);
// result is array(12, 10, 9, 0, 0)$result = array_pad($input, -7, -1);
// result is array(-1, -1, -1, -1, 12, 10, 9)$result = array_pad($input, 2, "noop");
// not padded
?>
See Also
- array_fill() - Fill an array with values
- range() - Create an array containing a range of
elements
tugla ¶
13 years ago
Beware, if you try to pad an associative array using numeric keys, your keys will be re-numbered.
<?php
$a = array('size'=>'large', 'number'=>20, 'color'=>'red');
print_r($a);
print_r(array_pad($a, 5, 'foo'));
// use timestamps as keys
$b = array(1229600459=>'large', 1229604787=>20, 1229609459=>'red');
print_r($b);
print_r(array_pad($b, 5, 'foo'));
?>
yields this:
------------------
Array
(
[size] => large
[number] => 20
[color] => red
)
Array
(
[size] => large
[number] => 20
[color] => red
[0] => foo
[1] => foo
)
Array
(
[1229600459] => large
[1229604787] => 20
[1229609459] => red
)
Array
(
[0] => large
[1] => 20
[2] => red
[3] => foo
[4] => foo
)
scott*hurring.com ¶
20 years ago
to the previous commenter -- if you read the manual entry, you'd see that a negative pad_size will put the pad values at the front of the array.
goffrie at sympatico dot ca ¶
19
years ago
To daarius - you mean you have...
[2]=>"two"
[3]=>"three"
and you want...
[0]=>"FILLED"
[1]=>"FILLED"
[2]=>"two"
[3]=>"three"
[4]=>"FILLED"
[5]=>"FILLED"
If so, then the following code...
<?php
$array = array(2 => "two", 3 => "three");
$array = array_pad($array, count($array)+2, "FILLED");
$num = -(count($array)+2);
$array = array_pad($array, $num, "FILLED");
print_r($array);
?>
will return:
Array ( [0] => FILLED [1] => FILLED [2] => two [3] => three [4] => FILLED [5] => FILLED )
The ordering should be okay,...
mwwaygoo at hotmail dot com ¶
18 years ago
little older, a little wiser.
ksort() will order the array back into its normal order again
so:
<?php
$myArr = array(2 => 'two', 4 => 'four');
$newArr = array_pad(array(), 6, 'FILLED');
$newArr =$myArr+$newArr;
ksort($newArr);
?>
Will give :
Array ( [0] => FILLED [1] => FILLED [2] => two [3] => FILLED [4] => four [5] => FILLED )
Anonymous ¶
18 years ago
One way to initialize a 20x20 multidimensional array.
<?php
$a = array();
$b = array();
$b = array_pad($b,20,0);
$a = array_pad($a,20,$b);
?>
daarius at hotmail dot
com ¶
20 years ago
yes that is true. But, if the index of the array is 2=two, 3=three
and i want 4 more keys to be filled. But, not just filled anywhere, but i want to maintain the key index.
so, i would like to have 0=FILLED, 1=FILLED ... 4=FILLED, 5=FILLED
now i got 4 more keys padded with my string.
We can do this "if" we know the missing keys, but if we dont, then it would be nice for array_pad() or perhaps some new function to do this?
obviously we can achive this by looping through the array using array_key_exists(), and if you dont find the key, simply create + fill it.
regards,
Daarius...
mwwaygoo at hotmail dot com ¶
20 years ago
OR you could do this
<?php
$myArr = array(2 => 'three', 3 => 'four');
$newArr = array_pad(array(), 4, 'FILLED');
$newArr =$myArr+$newArr;
?>
This gives your desired result BUT the ordering is a little wierd, because of the order they were added. Indexes are okay though and that is what you wanted.
print_r($newArr) outputs
Array ( [2] => three [3] => four [0] => FILLED [1] => FILLED )
hope this helps
oaev at mail dot ru ¶
17 years ago
Easy way to get an array contains 5 random numbers from 0 to 9:
$rand_arr = array_rand( array_pad( array(), 10, 1 ), 5 );
slava-san at mail dot ru ¶
9 years ago
// insert element to array
function array_insert(&$arr, $pos, $new_el=null) {
$arraypad = array_pad($arr, count($arr)+1, 0);
for ($i=count($arr)-1; $i>=$pos; $i--) {
$arr[$i+1] = $arr[$i];
if ($i == $pos) {
$arr[$i] = $new_el;
}
}
}
$digits = array();
$digits[0] = 0;
$digits[1] = 1;
$digits[2] = 2;
$digits[3] = 3;
$digits[4] = 4;
$digits[5] = 5;
echo "was: "; var_dump($digits);
array_insert($digits, 3, 100);
echo "new: "; var_dump($digits);
hk, StrApp Bussiness Solutions ¶
15
years ago
A simple example for array_pad()
the syntax is as follows: array_pad(array(), (+/-)int, value)
where "array" is the array to which the value is to be added,
"(+/-) int" is a value that decides the length of the array(it should be greater than the length of the array.
if its a negative number then the value will be added at the left of the array else it will be added to the right.
"values" denotes the value to be added to the array
lets try an example:
<?php
$digits
= array();
$digits[0] = 1;
$digits[1] = 2;
$digits[2] = 3;
$arraypad = array_pad($digits, -4, "0");
print_r($arraypad);?>
output:Array ( [0] => 0 [1] => 1 [2] => 2 [3] => 3 )
sonu50imedbvu at gmail dot com(Sonu Jaiswal) ¶
11 years ago
Just an info about the value of "$pad_size" ,
If we set the value of "$pad_size" from -3 to 3,
It will produce the output like:
<?php
$result = array_pad($input, -3, "noop");
//result is array(12, 10, 9)
$result = array_pad($input, 3, "noop");
//result is array(12, 10, 9)
?>
means array will remain the same.
