(PHP 4 >= 4.2.0, PHP 5)
array_fill — 用给定的值填充数组
array_fill() 用 value
参数的值将一个数组填充 num
个条目,键名由
start_index
参数指定的开始。
start_index
The first index of the returned array.
If start_index
is negative,
the first index of the returned array will be
start_index
and the following
indices will start from zero
(参见 例子)。
num
插入元素的数量。 必须大于 0。
value
Value to use for filling
Returns the filled array
如果 num
少于一个,将会抛出 E_WARNING
。
Example #1 array_fill() 例子
<?php
$a = array_fill(5, 6, 'banana');
$b = array_fill(-2, 4, 'pear');
print_r($a);
print_r($b);
?>
以上例程会输出:
Array ( [5] => banana [6] => banana [7] => banana [8] => banana [9] => banana [10] => banana ) Array ( [-2] => pear [0] => pear [1] => pear [2] => pear )
参见手册上 数组 一节里关于负数的键的详细解释。
miguelxpain at gmail dot com (2012-02-24 18:04:55)
I made this function named "array_getMax" that returns te maximum value and index, from array:
<?php
//using array_search_all by helenadeus at gmail dot com
function array_search_all($needle, $haystack)
{#array_search_match($needle, $haystack) returns all the keys of the values that match $needle in $haystack
foreach ($haystack as $k=>$v) {
if($haystack[$k]==$needle){
$array[] = $k;
}
}
return ($array);
}
function array_getMax($array){
$conteo=array_count_values($array);
if( count($conteo)==1 ){//returns full array when all values are the same.
return $array;
}
arsort($array);
//$antValue=null;
$maxValue=null;
$keyValue=null;
foreach($array as $key=>$value){
if($maxValue==null){
$maxValue=$value;
$keyValue=$key;
break;
}
}
$resultSearch=array_search_all($maxValue, $array);
return array_fill_keys($resultSearch, $maxValue);
}
//example
$arreglo=array('e1'=>99,'e2'=>'99','e3'=>1,'e4'=>1,'e5'=>98);
var_dump(array_getMax($arreglo));
//output
/*
array(2) {
["e1"]=>
int(99)
["e2"]=>
int(99)
}
*/
?>
I hope some one find this usefull
caliban at darklock dot com (2005-05-23 07:42:14)
To better handle the problem of sparse array completion mentioned a couple years ago...
What you really need in this scenario is an empty array containing all the desired keys, and a sparse array containing the keys and values you want overridden. This PHP5 function does that. (The PEAR package PHP_Compat should be able to fill in the gap -- array_combine() -- for a 4.3 install, if necessary.)
<?php
function array_complete(
$keys="", // array of keys you need filled, in order
$sparse="" // sparse array to override blanks
)
{
if(!is_array($sparse))
$sparse=array();
if(!is_array($keys))
return $sparse;
return array_merge(
array_combine( // create an associative array
$keys, // your list of keys
array_fill( // blank value for each key
0,count(
$keys
),""
)
),$sparse // merge with your incomplete array
);
}
?>
This merges in your sparse array (inserting any additional keys in that array after the ones you've specified), placing its values in the key order you specify, leaving all the other values blank.
Test call: var_dump(array_complete(array("test1", "test2", "test3", "test4", "test5"), array("test3" => "test3", "test1" => "test1", "garbage" => "garbage")));
Result: array(6) {
["test1"]=>
string(5) "test1"
["test2"]=>
string(0) ""
["test3"]=>
string(5) "test3"
["test4"]=>
string(0) ""
["test5"]=>
string(0) ""
["garbage"]=>
string(7) "garbage"
}
csst0266 at cs dot uoi dot gr (2004-08-11 10:32:39)
This is what I recently did to quickly create a two dimensional array (10x10), initialized to 0:
<?php
$a = array_fill(0, 10, array_fill(0, 10, 0));
?>
This should work for as many dimensions as you want, each time passing to array_fill() (as the 3rd argument) another array_fill() function.
jausion at hotmail-dot-com (2003-03-28 23:50:51)
For PHP < 4.2.0 users:
Add this to your script:
if (!function_exists('array_fill')) {
require_once('array_fill.func.php');
}
and the array_fill.func.php file:
<?php
// For PHP version < 4.2.0 missing the array_fill function,
// I provide here an alternative. -Philippe
function array_fill($iStart, $iLen, $vValue) {
$aResult = array();
for ($iCount = $iStart; $iCount < $iLen + $iStart; $iCount++) {
$aResult[$iCount] = $vValue;
}
return $aResult;
}
?>
(2002-08-25 13:59:46)
array_fill() cannot be used to setup only missing keys in an array. This may be necessary for example before using implode() on a sparse filled array.
The solution is to use this function:
<?php
function array_setkeys(&$array, $fill = NULL) {
$indexmax = -1;
for (end($array); $key = key($array); prev($array)) {
if ($key > $indexmax)
$indexmax = $key;
}
for ($i = 0; $i <= $indexmax; $i++) {
if (!isset($array[$i]))
$array[$i] = $fill;
}
ksort($array);
}
?>
This is usefull in some situations where you don't know which key index was filled and you want to preserve the association between a positioned field in an imploded array and the key index when exploding it.