array_pad

(PHP 4, PHP 5)

array_pad — Expande um array para um certo comprimento utilizando um determinado valor

Descrição

array array_pad ( array $input , int $pad_size , mixed $pad_value )

array_pad() retorna uma cópia de input expandido para o comprimento especificado por pad_size com o valor pad_value . Se pad_size for positivo então o array é expandido pela direita, se for negativo, pela esquerda. Se o valor absoluto de pad_size for menor ou igual ao comprimento de input , então ele permanece inalterado. É possível adicionar até 1048576 elementos de uma vez.

Parâmetros

input: Array inicial de valores para ser preenchido.
pad_size: Nova tamanho do array.
pad_value: Valor para preencher se input é menor que pad_size .

Valor Retornado

Retorna uma cópia de input preenchido pela quantidade especificada por pad_size com o valor pad_value . Se pad_size é positivo, então o array é preenchido na direita, se ele é negativo, então da esquerda. Se o valor absoluto de pad_size é menor que ou igual ao tamanho da entrada, então nenhum preenchimento ocorre.

Exemplos

Exemplo #1 Exemplo de array_pad()


<?php
$input = array(12, 10, 9);

$result = array_pad($input, 5, 0);
// $result é array(12, 10, 9, 0, 0)

$result = array_pad($input, -7, -1);
// $result é array(-1, -1, -1, -1, 12, 10, 9)

$result = array_pad($input, 2, "noop");
// Não será expandido
?>

Veja Também

array_pop

array_multisort

Last updated: Fri, 14 Nov 2008

add a note User Contributed Notes
array_pad

hk, StrApp Bussiness Solutions
08-Jan-2007 02:15


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 )

oaev at mail dot ru
21-Oct-2004 11:48


Easy way to get an array contains 5 random numbers from 0 to 9:



$rand_arr = array_rand( array_pad( array(), 10, 1 ), 5 );

28-Feb-2004 09:00


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);


?>

mwwaygoo at hotmail dot com
16-Jan-2004 08:02


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 )

goffrie at sympatico dot ca
23-Mar-2003 05:06


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
19-Sep-2002 09:39


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

daarius at hotmail dot com
23-Jul-2002 07:36


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...

scott*hurring.com
19-Jul-2002 04:20


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.

ethanhunt314 at hotmail dot com
10-Dec-2000 04:25


This is useful when using next() and prev() function in a while loop to traverse an array. 





For example the following code will only output up to 8.





<?php


$test[] = "1";


$test[] = "2";


$test[] = "3";


$test[] = "4";


$test[] = "5";


$test[] = "6";


$test[] = "7";


$test[] = "8";


$test[] = "9";


$test[] = "10";


$test[] = " ";


$test[] = " ";


$test[] = " ";





$count = count($test);





while($i < $count) {





$now = current($test);


echo "<p>$now</p>";





next($test);


next($test);


next($test);


prev($test);


prev($test);


prev($test);








$i++;


next($test);


}


?>





But if you use:


$test = array_pad($test, 13, " ");





you will get all of your output.

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array_pop

array_multisort

Last updated: Fri, 14 Nov 2008