<?php
$a = array("1");
var_dump(array_fill_keys($a, "test"));
?>
array(1) {
[1]=>
string(4) "test"
}
now string key "1" become an integer value 1, be careful.
(PHP 5 >= 5.2.0, PHP 7, PHP 8)
array_fill_keys — 使用指定的键和值填充数组
keys使用该数组的值作为键。非法值将被转换为字符串。
value填充使用的值。
返回填充后的数组。
示例 #1 array_fill_keys() 示例
<?php
$keys = array('foo', 5, 10, 'bar');
$a = array_fill_keys($keys, 'banana');
print_r($a);
?>以上示例会输出：
Array
(
[foo] => banana
[5] => banana
[10] => banana
[bar] => banana
)
<?php
$a = array("1");
var_dump(array_fill_keys($a, "test"));
?>
array(1) {
[1]=>
string(4) "test"
}
now string key "1" become an integer value 1, be careful.Get an associative array of zeros for counting letter frequency
<?php
$ltrs = array_fill_keys( range('a', 'z'), 0 );If an associative array is used as the second parameter of array_fill_keys, then the associative array will be appended in all the values of the first array.
e.g.
<?php
$array1 = array(
"a" => "first",
"b" => "second",
"c" => "something",
"red"
);
$array2 = array(
"a" => "first",
"b" => "something",
"letsc"
);
print_r(array_fill_keys($array1, $array2));
?>
The output will be
Array(
[first] => Array(
[a] => first,
[b] => something,
[0] => letsc
),
[second] => Array(
[a] => first,
[b] => something,
[0] => letsc
),
[something] => Array(
[a] => first,
[b] => something,
[0] => letsc
),
[red] => Array(
[a] => first,
[b] => something,
[0] => letsc
)
)RE: bananasims at hotmail dot com
I also needed a work around to not having a new version of PHP and wanting my own keys. bananasims code doesn't like having an array as the second parameter...
Here's a slightly modified version than can handle 2 arrays as inputs:
//we want these values to be keys
$arr1 = (0 => "abc", 1 => "def");
/we want these values to be values
$arr2 = (0 => 452, 1 => 128);
function array_fill_keys($keyArray, $valueArray) {
if(is_array($keyArray)) {
foreach($keyArray as $key => $value) {
$filledArray[$value] = $valueArray[$key];
}
}
return $filledArray;
}
array_fill_keys($arr1, $arr2);
returns:
abc => 452, def =>128Some of the versions do not have this function.
I try to write it myself.
You may refer to my script below
function array_fill_keys($array, $values) {
if(is_array($array)) {
foreach($array as $key => $value) {
$arraydisplay[$array[$key]] = $values;
}
}
return $arraydisplay;
}This function does the same as:
<?php
$array = array_combine($keys,array_fill(0,count($keys),$value));
?>Scratchy's version still doesn't work like the definition describes. Here's one that can take a mixed variable as the second parameter, defaulting to an empty string if it's not specified. Don't know if this is exactly how the function works in later versions but it's at least a lot closer.
function array_fill_keys($target, $value = '') {
if(is_array($target)) {
foreach($target as $key => $val) {
$filledArray[$val] = is_array($value) ? $value[$key] : $value;
}
}
return $filledArray;
}
This works for either strings or numerics, so if we have
$arr1 = array(0 => 'abc', 1 => 'def');
$arr2 = array(0 => 452, 1 => 128);
$arr3 = array(0 => 'foo', 1 => 'bar');
then
array_fill_keys($arr1,$arr2)
returns: [abc] => 452, [def] => 128
array_fill_keys($arr1,0)
returns: [abc] => 0, [def] => 0
array_fill_keys($arr2,$arr3)
returns: [452] => foo, [128] => bar
array_fill_keys($arr3,'BLAH')
returns: [foo] => BLAH, [bar] => BLAH
and array_fill_keys($arr1)
returns: [abc] =>, [def] =>To remove arbitrary keys from an associative array:
<?php
function nuke_keys($keys, $array) {
return array_diff_key($array, array_fill_keys($keys, 0));
}
$array = array('blue' => 1, 'red' => 2, 'green' => 3, 'purple' => 4);
$keys = array('red', 'purple');
print_r(nuke_keys($keys, $array));
?>
The above snippet will return:
Array
(
[blue] => 1
[green] => 3
)see array_fill_keys are basically used to make a new array from a pre-existing array in a form that the value of the pre-existing array will now be the key of the new Array .And there value will be same That we had given in the 2nd parameter . Example Below---->>>
<?php
//pre existing array
$a = array("a","b","c","d","e");
//new array with a single same value
$newArray = array_fill_keys($a, "Testing");
//printing the array
echo "<pre>";
print_r($newArray);
echo "</pre>";
?>
output;
Array
(
[a] => Testing
[b] => Testing
[c] => Testing
[d] => Testing
[e] => Testing
)$keys = array(1, 2, 3);
// Fill it with value.
$keys = array_fill_keys($keys, 'banana');
print_r($keys);
// Fill it different value.
$apples = array_fill_keys(array_keys($keys), 'apple');
print_r($apples);
// Output:
Array (
[1] => banana
[2] => banana
[3] => banana
)
Array (
[1] => apple
[2] => apple
[3] => apple
)