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(PHP 4, PHP 5)
array_splice — Entfernt einen Teil eines Arrays und ersetzt ihn durch etwas anderes
Entfernt die durch offset und length angegebenen Elemente aus dem Array input, und ersetzt diese durch die Elemente des Arrays replacement, wenn angegeben.
Beachten Sie, dass numerische Schlüssel in input nicht erhalten werden.
Hinweis: Wenn replacement kein Array ist, wird es in ein Array umgewandelt (dies entspricht
(array) $parameter). Dies kann zu unerwartetem Verhalten führen, wenn replacement ein Objekt oder NULL ist.
Das Eingabe-Array.
Ist offset positiv, beginnt der zu entfernende Bereich bei diesem Offset vom Anfang des Arrays input. Ist offset negativ, beginnt der zu entfernende Bereich so viele Elemente vor dem Ende des Arrays input.
Ist length nicht angegeben, wird alles von offset bis zum Ende des Arrays entfernt. Ist length angegeben und positiv, werden so viele Elemente entfernt. Ist length angegeben und negativ, so ist das Ende des entfernten Bereichs so viele Elemente vor dem Ende des Array. Tipp: Um alles von offset bis zum Ende des Arrays zu entfernen, wenn replacement ebenfalls angegeben ist, verwenden Sie count($input) als length.
Ist das Array replacement angegeben, werden die entfernten Elemente durch die Elemente dieses Arrays ersetzt.
Sind offset und length so angegeben, dass nichts entfernt wird, werden die Elemente von replacement an der von offset spezifizierten Stelle eingefügt. Beachten Sie, dass Schlüssel bei der Ersetzung nicht erhalten werden.
Wenn replacement nur aus einem Element besteht, ist es nicht notwendig, array() anzugeben, sofern das Element nicht selbst ein Array, ein Objekt odr NULL ist.
Gibt ein Array zurück, das aus den ausgeschnittenen Elementen besteht.
Beispiel #1 array_splice()-Beispiele
<?php
$input = array("rot", "grün", "blau", "gelb");
array_splice($input, 2);
// $input ist nun array("rot", "grün")
$input = array("rot", "grün", "blau", "gelb");
array_splice($input, 1, -1);
// $input ist nun array("rot", "gelb")
$input = array("rot", "grün", "blau", "gelb");
array_splice($input, 1, count($input), "orange");
// $input ist nun array("rot", "orange")
$input = array("rot", "grün", "blau", "gelb");
array_splice($input, -1, 1, array("schwarz", "braun"));
// $input ist nun array("rot", "grün",
"blau", "schwarz", "braun")
$input = array("rot", "grün", "blau", "gelb");
array_splice($input, 3, 0, "lila");
// $input is now array("rot", "grün",
// "blau", "lila", "gelb");
?>
Beispiel #2 array_splice()-Beispiele
Die folgenden Anweisungen ändern die Werte von $input auf die gleiche Weise:
<?php
array_push($input, $x, $y);
array_splice($input, count($input), 0, array($x, $y));
array_pop($input);
array_splice($input, -1);
array_shift($input);
array_splice($input, 0, 1);
array_unshift($input, $x, $y);
array_splice($input, 0, 0, array($x, $y));
$input[$x] = $y; // für Arrays, bei denen der Schlüssel dem Offset entspricht
array_splice($input, $x, 1, $y);
?>
If you want to append null values wrap them in an array:
<?php
$a = array('Hey', 'hey', 'my', 'my');
array_splice($a, 1, 0, null);
print_r($a);
?>
Array
(
[0] => Hey
[1] => hey
[2] => my
[3] => my
)
<?php
$b = array('Hey', 'hey', 'my', 'my');
array_splice($b, 1, 0, array(null));
print_r($b);
?>
Array
(
[0] => Hey
[1] =>
[2] => hey
[3] => my
[4] => my
)
Splicing with NULL as replacement may result in unexpected behavior too. Typecasting NULL into an array results in an empty array (as "(array)NULL" equals "array()"). That means, instead of creating an element with value NULL just no new element ist created (just as if there was no replacement specified).
If you want the splicing to create a new element with value NULL you have to use "array(NULL)" instead of NULL.
You should expect this if you read the explanation carefully, but just as objects are considered as a special case for replacement, NULL should be too.
The explanation of replacement better should read: "If replacement is just one element it is not necessary to put array() around it, unless the element is an array itself, an object or NULL."
And the note better should be: "If replacement is not an array, it will be typecast to one (i.e. (array) $parameter). This may result in unexpected behavior when using an object or NULL replacement."
jmtc
just useful functions to move an element using array_splice.
<?php
// info at danielecentamore dot com
// $input (Array) - the array containing the element
// $index (int) - the index of the element you need to move
function moveUp($input,$index) {
$new_array = $input;
if((count($new_array)>$index) && ($index>0)){
array_splice($new_array, $index-1, 0, $input[$index]);
array_splice($new_array, $index+1, 1);
}
return $new_array;
}
function moveDown($input,$index) {
$new_array = $input;
if(count($new_array)>$index) {
array_splice($new_array, $index+2, 0, $input[$index]);
array_splice($new_array, $index, 1);
}
return $new_array;
}
$input = array("red", "green", "blue", "yellow");
$newinput = moveUp($input, 2);
// $newinput is array("red", "blue", "green", "yellow")
$input = moveDown($newinput, 1);
// $input is array("red", "green", "blue", "yellow")
?>
Should you want a similar function for splicing strings together, here is a rough equivalent:
<?php
function str_splice($input, $offset, $length=null, $splice='')
{
$input = (string)$input;
$splice = (string)$splice;
$count = strlen($input);
// Offset handling (negative values measure from end of string)
if ($offset<0) $offset = $count + $offset;
// Length handling (positive values measure from $offset; negative, from end of string; omitted = end of string)
if (is_null($length)) $length = $count;
elseif ($length < 0) $length = $count-$offset+$length;
// Do the splice
return substr($input, 0, $offset) . $splice . substr($input, $offset+$length);
}
$string = "The fox jumped over the lazy dog.";
// Outputs "The quick brown fox jumped over the lazy dog."
echo str_splice($string, 4, 0, "quick brown ");
?>
Obviously this is not for cases where all you need to do is a simple search-and-replace.
I need <?php array_Splice()?> function, that use array keys instead of order (offset and length) because of associated arrays, and this is result:
<?php
/**
* first variation
*
* $input is input array
* $start is index of slice begin
* $end is index of slice end, if this is null, $replacement will be inserted (in the same way as original array_Slice())
*indexes of $replacement are preserved in both examples
*/
function array_KSplice1(&$input, $start, $end=null, $replacement=null)
{
$keys=array_Keys($input);
$values=array_Values($input);
if($replacement!==null)
{
$replacement=(array)$replacement;
$rKeys=array_Keys($replacement);
$rValues=array_Values($replacement);
}
$start=array_Search($start,$keys,true);
if($start===false)
return false;
if($end!==null)
{
$end=array_Search($end,$keys,true);
// if $end not found, exit
if($end===false)
return false;
// if $end is before $start, exit
if($end<$start)
return false;
// index to length
$end-=$start-1;
}
// optional arguments
if($replacement!==null)
{
array_Splice($keys,$start,$end,$rKeys);
array_Splice($values,$start,$end,$rValues);
}
else
{
array_Splice($keys,$start,$end);
array_Splice($values,$start,$end);
}
$input=array_Combine($keys,$values);
return $input;
}
/**
* second variation
*
* $input is input array
* $start is index of slice begin
* $length is length of slice, what will be replaced, if is zero, $replacement will be inserted (in the same way as original array_Slice())
*/
function array_KSplice2(&$input, $start, $length=0, $replacement=null)
{
$keys=array_Keys($input);
$values=array_Values($input);
if($replacement!==null)
{
$replacement=(array)$replacement;
$rKeys=array_Keys($replacement);
$rValues=array_Values($replacement);
}
$start=array_Search($start,$keys,true);
if($start===false)
return false;
// optional arguments
if($replacement!==null)
{
array_Splice($keys,$start,$length,$rKeys);
array_Splice($values,$start,$length,$rValues);
}
else
{
array_Splice($keys,$start,$length);
array_Splice($values,$start,$length);
}
$input=array_Combine($keys,$values);
return $input;
}
$array=range(1,10);
var_Dump(array_KSplice1($array,3,3,array(100=>101,102,103,104)));
$array=range(1,10);
var_Dump(array_KSplice2($array,3,3,array(100=>101,102,103,104)));
?>
Both examples output:
array(11) {
[0]=>
int(1)
[1]=>
int(2)
[2]=>
int(3)
[100]=>
int(101)
[101]=>
int(102)
[102]=>
int(103)
[103]=>
int(104)
[6]=>
int(7)
[7]=>
int(8)
[8]=>
int(9)
[9]=>
int(10)
}
If you have multidimensional array like
<?php
$arr = array(array("a"=>1,"b"=>2),array("a"=>7,"b"=>-34));
?>
you can insert elements using array(array(...)). For example:
<?php
array_splice($arr, 1, 0, array(array("a"=>100, "b"=>77)))
?>
Note: If replacement is not an array, it will be typecast to one (i.e. (array) $parameter). This may result in unexpected behavior when using an object replacement .
Example :
<?php
class A()
{
private $a;
private $b;
public function __construct()
{
$this->a = "foo";
$this->b = "bar";
}
}
$array = array();
array_splice($array, 0, 0, new A());
print_r($array);
?>
Outputs :
Array : Array
{
[0] => foo
[1] => bar
}
Solution : Enforce the array() on the object.
<?php
array_splice($array, 0, 0, array(new Object());
?>
Source : http://bugs.php.net/bug.php?id=44485
i miss posted the actual function...
here is the real one lol
<?php
function q_sort(&$Info, $Index, $Left, $Right)
{
echo "memory usage <b>".memory_get_usage()."</b><br/>\n";
$L_hold = $Left;
$R_hold = $Right;
$Pivot = $Left;
$PivotValue = $Info[$Left];
while ($Left < $Right)
{
while (($Info[$Right][$Index] >= $PivotValue[$Index]) && ($Left < $Right))
$Right--;
if ($Left != $Right)
{
$Info[$Left] = $Info[$Right];
$Left++;
}
while (($Info[$Left][$Index] <= $PivotValue[$Index]) && ($Left < $Right))
$Left++;
if ($Left != $Right)
{
$Info[$Right] = $Info[$Left];
$Right--;
}
}
$Info[$Left] = $PivotValue;
$Pivot = $Left;
$Left = $L_hold;
$Right = $R_hold;
if ($Left < $Pivot)
q_sort($Info, $Index, $Left, $Pivot-1);
if ($Right > $Pivot)
q_sort($Info, $Index, $Pivot+1, $Right);
}
?>
Do you need to sort a 2D array on just one of its variables while trying to preserve somewhat the original order?
<?php
function sort_2d_array($array, $position, $order = "ASC"){
if (!is_array($array)) return $array;
if (count($array) < 2) return $array;
$new = array($array[0]);
for ($cnt = 1; $cnt <= count($array) - 1; $cnt++){
$stop = 0;
$splice = 0;
for ($newcnt = 0; $newcnt <= count($new) - 1; $newcnt++){
if ($stop == 0){
if ($order == "ASC")
if ($array[$cnt][$position] < $new[$newcnt][$position]){
$splice = $newcnt;
$stop = 1;
} // splice position for ASC
if ($order == "DESC")
if ($array[$cnt][$position] > $new[$newcnt][$position]){
$splice = $newcnt;
$stop = 1;
} // splice position for DESC
} // stop vying for position
} // cycle through new array to find position
if ($stop == 0){
$new[] = $array[$cnt];
} else {
array_splice($new, $splice, 0, array($array[$cnt]));
} // splice into new array while keeping somewhat the original order
} // cycle through original array
return $new;
} // sort_2d_array
?>
Application Example: In-House Search Engine
Here we are trying to find the word apple in the website by sort of the most recent occurances first, but the number of occurances first.
We've already sorted the mysql output by the date desc and have counted the no of occurances and have placed those in an array for the final query.
I've used this function to further sort the occurances but somewhat keep the original mysql sort order.
Key
[0] Record number
[0] Record ID
[1] Source Table
[2] No of Occurances Pinged
---------------------------
[0]
[0] 24530
[1] Blogs
[2] 1
[1]
[0] 24400
[1] Blogs
[2] 1
[2]
[0] 24240
[1] Blogs
[2] 4
[3]
[0] 243422
[1] Classifieds
[2] 1
[4]
[0] 243100
[1] Classifieds
[2] 1
After running...
<?php
sort_2d_array($array, 2, "DESC");
?>
We have...
[0]
[0] 24240
[1] Blogs
[2] 4
[1]
[0] 24530
[1] Blogs
[2] 1
[2]
[0] 24400
[1] Blogs
[2] 1
[3]
[0] 243422
[1] Classifieds
[2] 1
[4]
[0] 243100
[1] Classifieds
[2] 1
Might be useful to someone...
array_splice($input, -1) / array_slice($input, 1) equivalent to array_shift($input) ?????
Try this:
<?php
$input = array('key1' => array('deep1' => 'Value'), 'key2' => array('deep2' => 'Value'), 'key3' => array('deep3' => 'Value'));
$foo_splice = array_splice($input, -1);
$foo_shift = array_shift($input);
echo "<pre>".print_r($foo_splice, true)."</pre>";
echo "<pre>".print_r($foo_shift, true)."</pre>";
?>
Output:
Array
(
[key3] => Array
(
[deep3] => Value
)
)
Array
(
[deep1] => Value
)
Here's my own take on an array slice method that preserves keys from an associative array.
<?php
/**
* Array slice function that preserves associative keys
*
* @function associativeArraySlice
*
* @param Array $array Array to slice
* @param Integer $start
* @param Integer $end
*
* @return Array
*/
function associativeArraySlice($array, $start, $end) {
// Method param restrictions
if($start < 0) $start = 0;
if($end > count($array)) $end = count($array);
// Process vars
$new = Array();
$i = 0;
// Loop
foreach($array as $key => $value) {
if($i >= $start && $i < $end) {
$new[$key] = $value;
}
$i++;
}
return($new);
}
?>
for inserting array in 2-d array, according x position, y position
<?php
function add_module_xy($x_loc, $y_loc, $module) {
//identify the column of the modules
switch ($x_loc) {
case 1:
$x = 'left';
break;
case 2:
$x = 'middle';
break;
case 3:
$x = 'right';
break;
default:
throw new Exception("", "Invalid horizontal position $x_loc");
}
$max_y_loc = count($this->module_arrays[$x]) + 1;
if ($y_loc > $max_y_loc) {
//if y location is greater then max array index then add module to last
$y_loc = $max_y_loc;
}
$left = array_slice ($this->module_arrays[$x], 0, $y_loc-1);
$right = array_slice ($this->module_arrays[$x], $y_loc-1);
$insert[0] = $module;
$array = array_merge ($left, $insert, $right);
$this->module_arrays[$x] = $array;
}
?>
Ever wounder what array_splice is doing to your references, then try this little script and see the output.
<?php
$a = "a";
$b = "b";
$c = "c";
$d = "d";
$arr = array();
$arr[] =& $a;
$arr[] =& $b;
$arr[] =& $c;
array_splice($arr,1,0,array($d));
$sec_arr = array();
$sec_arr[] =& $d;
array_splice($arr,1,0,$sec_arr);
$arr[0] = "test"; // should be $a
$arr[3] = "test2"; // should be $b
$arr[1] = "this be d?"; // should be $d
$arr[2] = "or this be d?"; // should be $d
var_dump($arr);
var_dump($a);
var_dump($b);
var_dump($d);
?>
The output will be (PHP 4.3.3):
array(5) {
[0]=>
&string(4) "test"
[1]=>
&string(10) "this be d?"
[2]=>
string(13) "or this be d?"
[3]=>
&string(5) "test2"
[4]=>
&string(1) "c"
}
string(4) "test"
string(5) "test2"
string(10) "this be d?"
So array_splice is reference safe, but you have to be careful about the generation of the replacement array.
have fun, cheers!
A comment on array_merge mentioned that array_splice is faster than array_merge for inserting values. This may be the case, but if your goal is instead to reindex a numeric array, array_values() is the function of choice. Performing the following functions in a 100,000-iteration loop gave me the following times: ($b is a 3-element array)
array_splice($b, count($b)) => 0.410652
$b = array_splice($b, 0) => 0.272513
array_splice($b, 3) => 0.26529
$b = array_merge($b) => 0.233582
$b = array_values($b) => 0.151298
Someone might find this function usefull. It just takes a given element from the array and moves it before given element into the same array.
<?php
function array_move($which, $where, $array)
{
$tmp = array_splice($array, $which, 1);
array_splice($array, $where, 0, $tmp);
return $array;
}
?>
In PHP 4.3.10, at least, it seems that elements that are inserted as part of the replacement array are inserted BY REFERENCE (that is, as though with the =& rather than = assignment operation). So if your replacement array contains elements that references to variables that you can also access via other variable name, then this will be true of the elements in the final array too.
In particular, this means that it is safe to use array_splice() on arrays of objects, as you won't be creating copies of the objects (as it is so easy to do in PHP 4).
For anybody who is wondering... jrhardytwothousandtwo's trick for inserting an element using array_splice, will also work with multi-dimensional arrays if you do the following:
<?php
function array_insert(&$input, $offset, $replacement){
array_splice($input, $offset, 0, 0);
$input[$offset] = $replacement;
}
?>
I'm not sure if this (or a derivative of it) will solve other problems that I have seen just about everybody on here trying to solve. But apart from it's hackish nature, it works well for me.
weikard's function below is useful but it will still strip keys from array elements where the key is an integer, whether or not it is in a string:
<?php
function array_insert (&$array, $position, $insert_array) {
$first_array = array_splice ($array, 0, $position);
$array = array_merge ($first_array, $insert_array, $array);
}
$f = array("three" => "zzz", "3" => "yyy");
$a = array("4.0" => "zzzz", "four" => "yyyy");
array_insert($a,0,$f);
var_dump($a);
// array(4) { ["three"]=> string(3) "zzz" [0]=> string(3) "yyy" ["4.0"]=> string(4) "zzzz" ["four"]=> string(4) "yyyy" }
?>
You cannot insert with array_splice an array with your own key. array_splice will always insert it with the key "0".
<?php
// [DATA]
$test_array = array (
row1 => array (col1 => 'foobar!', col2 => 'foobar!'),
row2 => array (col1 => 'foobar!', col2 => 'foobar!'),
row3 => array (col1 => 'foobar!', col2 => 'foobar!')
);
// [ACTION]
array_splice ($test_array, 2, 0, array ('rowX' => array ('colX' => 'foobar2')));
echo '<pre>'; print_r ($test_array); echo '</pre>';
?>
[RESULT]
Array (
[row1] => Array (
[col1] => foobar!
[col2] => foobar!
)
[row2] => Array (
[col1] => foobar!
[col2] => foobar!
)
[0] => Array (
[colX] => foobar2
)
[row3] => Array (
[col1] => foobar!
[col2] => foobar!
)
)
But you can use the following function:
function array_insert (&$array, $position, $insert_array) {
$first_array = array_splice ($array, 0, $position);
$array = array_merge ($first_array, $insert_array, $array);
}
<?php
// [ACTION]
array_insert ($test_array, 2, array ('rowX' => array ('colX' => 'foobar2')));
echo '<pre>'; print_r ($test_array); echo '</pre>';
?>
[RESULT]
Array (
[row1] => Array (
[col1] => foobar!
[col2] => foobar!
)
[row2] => Array (
[col1] => foobar!
[col2] => foobar!
)
[rowX] => Array (
[colX] => foobar2
)
[row3] => Array (
[col1] => foobar!
[col2] => foobar!
)
)
[NOTE]
The position "0" will insert the array in the first position (like array_shift). If you try a position higher than the langth of the array, you add it to the array like the function array_push.
Appending arrays
If you have an array $a2 whose values you would like to append to an array $a1 then four methods you could use are listed below in order of increasing time. The last two methods took significantly more time than the first two. The most surprising lesson is that using the & incurs a time hit.
<?php
foreach ($a2 as $elem) $a1[]=$elem;
foreach ($a2 as &$elem) $a1[]=$elem;
array_splice ($a1, count($a1), 0, $a2);
$a1 = array_merge($a1, $a2);
?>
Csaba Gabor from Vienna
To split an associative array based on it's keys, use this function:
<?php
function &array_split(&$in) {
$keys = func_get_args();
array_shift($keys);
$out = array();
foreach($keys as $key) {
if(isset($in[$key]))
$out[$key] = $in[$key];
else
$out[$key] = null;
unset($in[$key]);
}
return $out;
}
?>
Example:
<?php
$testin = array('a' => 1, 'b' => 2, 'c' => 3, 'd' => 4);
$testout =& array_split($testin, 'a', 'b', 'c');
print_r($testin);
print_r($testout);
?>
Will print:
Array
(
[d] => 4
)
Array
(
[a] => 1
[b] => 2
[c] => 3
)
Hope this helps anyone!
array_splice dynamically updates the total number of entries into the array. So for instance I had a case where I needed to insert a value into every 4th entry of the array from the back. The problem was when it added the first, because the total number was dynamically updated, it would only add after the 3rd then the 2nd and so one. The solution I found is to track the number of inserts which were done and account for them dynamically.
Code:
<?php
$modarray = array_reverse($mili);
$trig=1;
foreach($modarray as $rubber => $glue) {
if($rubber!="<BR>") {
$i++;
$b++;
if ($i==4) {
$trig++;
if($trig<=2) {
array_splice($modarray,$b,0,"<BR>");
}elseif($trig>=3){
array_splice($modarray,$b+($trig-2),0,"<BR>");
}
$i=0;
};
};
};
$fixarray = array_reverse($modarray);
?>
This function will preserve keys:
<?php
function my_array_splice(&$_arr, $_index, $_long){
$_keys=array_keys($_arr);
$_key=array_search($_index, $_keys);
if ( $_key !== FALSE ){
$_keys=array_splice($_keys, $_key, $_long);
foreach ($_keys as $_key) unset($_arr[$_key]);
}
}
?>
Be careful, array_splice does not behave like you might expect should you try to pass it an object as the replacement argument. Consider the following:
<?php
//Very truncated
class Tree {
var $childNodes
function addChild($offset, $node) {
array_splice($this->childNodes, $offset, 0, $node);
//...rest of function
}
}
class Node {
var $stuff
...
}
$tree = new Tree();
// ...set 2 nodes using other functions...
echo (count($tree->childNodes)); //Gives 2
$newNode = new Node();
// ...set node attributes here...
$tree->addChild(1, $newNode);
echo(count($tree->childNodes)); //Expect 3? wrong!
?>
In this case, the array has a number of items added to it equal to the number of attributes in the new Node object and the values thereof I.e, if your Node object has 2 attributes with values "foo" and "bar", count($tree->childNodes) will now return 4, with the items "foo" and "bar" added to it. I'm not sure if this qualifies as a bug, or is just a byproduct of how PHP handles objects.
Here's a workaround for this problem:
function array_insertobj(&$array, $offset, $insert) {
$firstPart = array_slice($array, 0, $offset);
$secondPart = array_slice($array, $offset);
$insertPart = array($insert);
$array = array_merge($firstPart, $insertPart, $secondPart);
}
Note that this function makes no allowances for when $offset equals the first or last index in the array. That's because array_unshift and array_push work just fine in those cases. It's only array_splice that can trip you up. Obviously, this is kinda tailor-made for arrays with numeric keys when you don't really care what said keys are, but i'm sure you could adapt it for associative arrays if you needed it.
Want to insert a new value in the middle of the array, without overwriting other elements? Try this.
<?php
$array = array(
0 => 0,
1 => 1,
2 => 2,
3 => 3,
4 => 4,
5 => 5
);
array_splice($array, 3, count($array), array_merge(array('x'), array_slice($array, 3)));
echo '<pre>';
print_r($array);
?>
Output:
Array
(
[0] => 0
[1] => 1
[2] => 2
[3] => x
[4] => 3
[5] => 4
[6] => 5
)
As you can see, the operation add 'X' in the 4th place, pushing everything else to the next key.
[ Editor's Note: If you're not concerned with the indexes being contiguously numbered (such as for an associative array) then unset($ar[$ind]); will accomplish the same as the code below without requiring splice/splice/merge. If contiguous numbering IS a concern (such as for indexed arrays), you can still save time by using: unset($ar[$ind]); $ar = array_values($ar); ]
Removing elements from arrays
This works better - much quicker
<?php
$ar = array("einstein", "bert", "colin", "descartes", "renoir");
$a = array_slice($ar, 0, $ind);
$b = array_slice($ar, $ind + 1);
$ar = array_merge($a, $b);
?>
key-safe:
<?php
function array_kslice ($array, $offset, $length = 0) {
$k = array_slice (array_keys ($array), $offset, $length);
$v = array_slice (array_values ($array), $offset, $length);
for ($i = 0; $i < count ($k); $i ++) $r[$k[$i]] = $v[$i];
return $r;
}
?>
smth like this. hope you like it more than versions above :)
It is possible to use a string instead of offset, eg if you want to deletre the entry $myArray['entry'] then you can simply do it like this:
<?php
array_splice($myArray, 'entry', 1);
?>
Note that you can use unset($myArray['entry']) as well but then, it doesn't enable you to remove more than one entry and it doesn't replace anything in the array, if that's what you intend to do.
Please note that array_splice() 's second argument is an OFFSET and not an INDEX.
Lets say you want to
$array_of_items = array ('nothing','myitem','hisitem','heritem');
$sid = array_search('myitem',$array_of_items);
echo $sid; /* prints out 1, since index element 1 is "myitem" */
Now, lets say we want to remove that "myitem" from the array:
<?php
$array_of_items = array_splice($array_of_items,(1+$sid),1);
?>
Notice how you have to add a one to the $sid variable? That is because offset item 1 is "nothing" and since $sid is currently 1 (the index of "myitem"), we add 1 more to it to find out
its OFFSET.
DO NOT DO THIS:
$array_of_items = array_splice($array_of_items,$sid,1);
to kokos@lac.lviv.ua:
Good point about the code not doing what you expected.
The failure to check for the insert case like you pointed out is not a bug, however. I didn't add code to handle that because the key of such an added index is more or less undefined in an unordered associative array. Put another way, if your array is associative and not auto-indexed, you most likely care enough about your keys to want to set them explicitly.
To paule@cs.tamu.edu :
Sorry, but the fix will still not work properly - when $length=0 (e.g. trying to insert one value) the
$new_array[$key]=$replacement;
would be immediately followed by
$new_array[$key]=$value;
and the $replacement will be lost.
What i was trying to point out in my original post is that $input[$x]=$y is NOT equivalent to array_splice($input, $x, 1, $y) . The equivalence mentioned would be true ONLY when $input is <... ghmm... > "automatically enumerated", having its' keys exactly matching offsets of corresponding elements in the array. But, in general case, keys do not match offsets - perhaps this should be explicitly stated in the Description above.
Aiya, I feel silly. The fix for my code above assumes that your values in the associative array are strings. Ignore the fix code in my last post and use this instead:
<?php
if(is_array($replacement))
foreach($replacement as $r_key=>$r_value)
$new_array[$r_key]=$r_value;
elseif($replacement!==NULL)
$new_array[$key]=$replacement;
?>
Sorry again. I feel sheepish. n.n
After reading KoKos' post above, I thought that the code I posted right before his should do what he wanted. However, my original post neglected to note the little "Tip" in the documentation above, about a single element replacement.
If one changes the lines in my code above that says:
<?php
if(is_array($replacement))
foreach($replacement as $r_key=>$r_value)
$new_array[$r_key]=$r_value;
?>
to instead say:
<?php
if(is_string($replacement))
$new_array[$key]=$replacement;
elseif(is_array($replacement))
foreach($replacement as $r_key=>$r_value)
$new_array[$r_key]=$r_value;
?>
that will solve the problem.
Sorry for the omission.
It may seem obvious from the above posts, but cost me a bit of
braindamage to figure this out...
Contrary to the equivalence noted on this page
$input[$x] = $y <==> array_splice ($input, $x, 1, $y)
array_splice() will not always work as expected,
even provided that you have only INTEGER keys!
The following code:
$t=array('a','b','c','d','e');
var_dump($t);
<?php
unset($t[0],$t[1],$t[3]);
$t[0]='f';
var_dump($t);
array_splice($t,0,1,'g');
var_dump($t);
?>
Will produce:
array(5) {
[0]=>
string(1) "a"
[1]=>
string(1) "b"
[2]=>
string(1) "c"
[3]=>
string(1) "d"
[4]=>
string(1) "e"
}
array(3) {
[2]=>
string(1) "c"
[4]=>
string(1) "e"
[0]=>
string(1) "f"
}
array(3) {
[0]=>
string(1) "g"
[1]=>
string(1) "e"
[2]=>
string(1) "f"
}
Note the position of $t[0] in the second call to var_dump().
And of course, array_splice() left it intact, changing $t[2] instead.
This is because it operates the _offset_, not the _index_. :)
I think that "equivalence note" should be considered buggy. ;)))
Best wishes.
KoKos.
I believe the following is a version of array_slice that solves most of the issues for people that want an associative key offset, rather than an integer.
<?php
function key_array_splice(&$input, $key_ofs, $length=NULL, $replacement=NULL)
{
// Adjust the length if it was negative or not passed
if($length===NULL || $length<0)
$count = $length+count($input);
// Cycle through the array
foreach($input as $key=>$value){
if(!$key_found){
if($key===$key_ofs){
$key_found=true;
if($length!==NULL && $length>=0)
$count=$length;
if(is_array($replacement))
foreach($replacement as $r_key=>$r_value)
$new_array[$r_key]=$r_value;
}else
$new_array[$key]=$value;
}
if($key_found){
if($count>0)
$ret_array[$key]=$value;
else
$new_array[$key]=$value;
}
$count--;
}
// Finish up
$input=$new_array;
return $ret_array;
}
?>
Note that this code needs PHP 4 for the use of the "===" and "!==" operators.
A reference is made to INSERT'ing into an array here with array_splice, however its not explained very well. I hope this example will help others find what took me days to research.
<?php
$original_array = array(1,2,3,4,5);
$insert_into_key_position = 3;
$item_to_insert = "blue";
$returned = array_splice($original_array, $insert_into_key_position, 0, $item_to_insert);
// $original_array will now show:
// 1,2,3,blue,4,5
?>
Remember that you are telling the array to insert the element into the KEY position. Thus the elements start with key 0 and so on 0=>1, 1=>2, 2=>3, 3=>blue, 4=>4, 5=>5. And walla, you've inserted. I can't say if this is of any value for named keys, or multidimensional arrays. However it does work for single dimensional arrays.
$returned should be an empty array as nothing was returned. This would have substance if you were doing a replace instead.
array_splice resets the internal pointer of $input. In fact, many array functions do this. Caveat programmor!
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