GeezerVison is showing www.php.net — PHP: array_slice - Manual
array_slice
(PHP 4, PHP 5, PHP 7, PHP 8) array_slice — Extract a slice of the array
Description
array_slice() returns the sequence of elements
from the array array as specified by the
offset and length
parameters.
Parameters
array
-
The input array.
offset
-
If offset is non-negative, the sequence will
start at that offset in the array.
If offset is negative, the sequence will
start that far from the end of the array.
Note:
The offset parameter denotes the position
in the array, not the key.
length
-
If length is given and is positive,
then the sequence will have up to that many elements in it.
If the array is shorter than the length,
then only the available array elements will be present.
If length is given and is negative then the
sequence will stop that many elements from the end of the array.
If it is omitted, then the sequence will have everything
from offset up until the end of the
array.
preserve_keys
-
Note:
array_slice() will reorder and reset the
integer array indices by default. This behaviour can be changed
by setting preserve_keys to true.
String keys are always preserved, regardless of this parameter.
Return Values
Returns the slice. If the offset is larger than the size of the array,
an empty array is returned.
Examples
Example #1 array_slice() examples
<?php
$input = array("a", "b", "c", "d", "e");
$output = array_slice($input, 2); // returns "c", "d", and "e"
$output = array_slice($input, -2, 1); // returns "d"
$output = array_slice($input, 0, 3); // returns "a", "b", and "c"
// note the differences in the array keys
print_r(array_slice($input, 2, -1));
print_r(array_slice($input, 2, -1, true));
?>
The above example will output:
Array
(
[0] => c
[1] => d
)
Array
(
[2] => c
[3] => d
)
Example #2 array_slice() and one-based array
<?php
$input = array(1 => "a", "b", "c", "d", "e");
print_r(array_slice($input, 1, 2));
?>
The above example will output:
Array
(
[0] => b
[1] => c
)
Example #3 array_slice() and array with mixed keys
<?php
$ar = array('a'=>'apple', 'b'=>'banana', '42'=>'pear', 'd'=>'orange');
print_r(array_slice($ar, 0, 3));
print_r(array_slice($ar, 0, 3, true));
?>
The above example will output:
Array
(
[a] => apple
[b] => banana
[0] => pear
)
Array
(
[a] => apple
[b] => banana
[42] => pear
)
taylorbarstow at the google mail service ¶20 years ago
Array slice function that works with associative arrays (keys):
function array_slice_assoc($array,$keys) {
return array_intersect_key($array,array_flip($keys));
}
Ray.Paseur often uses Gmail ¶13 years ago
<?php
// CHOP $num ELEMENTS OFF THE FRONT OF AN ARRAY
// RETURN THE CHOP, SHORTENING THE SUBJECT ARRAY
function array_chop(&$arr, $num)
{
$ret = array_slice($arr, 0, $num);
$arr = array_slice($arr, $num);
return $ret;
}
nathan dot fiscaletti at gmail dot com ¶8 years ago
If you want an associative version of this you can do the following:
function array_slice_assoc($array,$keys) {
return array_intersect_key($array,array_flip($keys));
}
However, if you want an inverse associative version of this, just use array_diff_key instead of array_intersect_key.
function array_slice_assoc_inverse($array,$keys) {
return array_diff_key($array,array_flip($keys));
}
Example:
$arr = [
'name' => 'Nathan',
'age' => 20,
'height' => 6
];
array_slice_assoc($arr, ['name','age']);
will return
Array (
'name' = 'Nathan',
'age' = 20
)
Where as
array_slice_assoc_inverse($arr, ['name']);
will return
Array (
'age' = 20,
'height' = 6
)
ted.devito at 9gmail9 dot 99com ¶18 years ago
based on worldclimb's arem(), here is a recursive array value removal tool that can work with multidimensional arrays.
function remove_from_array($array,$value){
$clear = true;
$holding=array();
foreach($array as $k => $v){
if (is_array($v)) {
$holding [$k] = remove_from_array ($v, $value);
}
elseif ($value == $v) {
$clear = false;
}
elseif($value != $v){
$holding[$k]=$v; // removes an item by combing through the array in order and saving the good stuff
}
}
if ($clear) return $holding; // only pass back the holding array if we didn't find the value
}
worldclimb at 99gmail99 dot com ¶18 years ago
array_slice can be used to remove elements from an array but it's pretty simple to use a custom function.
One day array_remove() might become part of PHP and will likely be a reserved function name, hence the unobvious choice for this function's names.
<?
function arem($array,$value){
$holding=array();
foreach($array as $k => $v){
if($value!=$v){
$holding[$k]=$v;
}
}
return $holding;
}
function akrem($array,$key){
$holding=array();
foreach($array as $k => $v){
if($key!=$k){
$holding[$k]=$v;
}
}
return $holding;
}
$lunch = array('sandwich' => 'cheese', 'cookie'=>'oatmeal','drink' => 'tea','fruit' => 'apple');
echo '<pre>';
print_r($lunch);
$lunch=arem($lunch,'apple');
print_r($lunch);
$lunch=akrem($lunch,'sandwich');
print_r($lunch);
echo '</pre>';
?>
(remove 9's in email)
Benjamin Sonntag ¶3 years ago
The documentation doesn't say it, but if LENGTH is ZERO, then the result is an empty array [].
developer at i-space dot org ¶24 years ago
remember that array_slice returns an array with the current element. you must use array_slice($array, $index+1) if you want to get the next elements.
s0i0m at dreamevilconcepts dot com ¶18 years ago
Using the varname function referenced from the array_search page, submitted by dcez at land dot ru. I created a multi-dimensional array splice function. It's usage is like so:
$array['admin'] = array('blah1', 'blah2');
$array['voice'] = array('blah3', 'blah4');
array_cut('blah4', $array);
...Would strip blah4 from the array, no matter where the position of it was in the array ^^ Returning this...
Array ( [admin] => Array ( [0] => blah1 [1] => blah2 ) [voice] => Array ( [0] => blah3 ) )
Here is the code...
<?php
function varname ($var)
{
// varname function by dcez at land dot ru
return (isset($var)) ? array_search($var, $GLOBALS) : false;
}
function array_cut($needle, $haystack)
{
foreach ($haystack as $k => $v)
{
for ($i=0; $i<count($v); $i++)
if ($v[$i] === $needle)
{
return array_splice($GLOBALS[varname($haystack)][$k], $i, 1);
break; break;
}
}
?>
Check out dreamevilconcept's forum for more innovative creations!
|