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(PHP 4, PHP 5)
end — Positioniert den internen Zeiger eines Arrays auf dessen letztes Element
end() rückt den internen Zeiger von array bis zum letzten Element vor, und gibt dessen Wert zurück.
Das Array.
Gibt den Wert des letzten Arrayelements zurück oder FALSE bei einem leeren Array.
Beispiel #1 end() example
<?php
$fruits = array('apple', 'banana', 'cranberry');
echo end($fruits); // cranberry
?>
An easy (and correct) way to get the last key:
$lastkey = array_pop(array_keys($arr));
It's interesting to note that when creating an array with numeric keys in no particular order, end() will still only return the value that was the last one to be created. So, if you have something like this:
<?php
$a = array();
$a[1] = 1;
$a[0] = 0;
echo end($a);
?>
This will print "0".
//fixing errors in last post...oops
//this is a function to move items in an array up or down
//in the array. it is done by breaking the array into two
//separate arrays and then have a loop creates the final array
//adding the item we want to move when the counter is equal
//to the new position we established
//the array key, position and direction were passed via a query string
//parameters
//$array- the array you are modifying
//$keytomove - the key of the item you wish to move
//$pos - the current position of the item: used a count($array) function
//and then loop with incrementing integer to add the position to the up //or down button
//$dir - the direction you want to move it - "up"/"dn"
function change_pos($array, $keytomove, $pos, $dir){
//count the original number of rows
$count = count($array);
//set the integer we will use to place the moved item
if($dir=="up"){
if($pos==1){
//if the item is already first and we try moving it up
//we send it to the end of the array
$change = $count;
}else{
//anywhere else it just moves back one closer to the start of the array
$change = $pos-1;
}
}
//do the same for the down button
if($dir=="dn"){
if($pos==$count){
$change = 1;
}else{
$change = $pos+1;
}
}
//copy the element that you wish to move
$move = $array[$keytomove];
//delete the original from the main array
unset($array[$keytomove]);
//create an array of the names of the values we
//are not moving
$preint = 1;
foreach($array as $c){
$notmoved["{$preint}"] = $c['name'];
$preint++;
}
//loop through all the elements
$int = 1;
while($int<=$count){
//dynamically change the key of the unmoved item as we increment the counter
$notmovedkey = $notmoved["$int"];
//when the counter is equal to the position we want
//to place the moved entry we pump it into a new array
if($int==$change){
$neworder["{$keytomove}"] = $move;
}
//add all the other array items if the position number is not met and
//resume adding them once the moved item is written
if($contkey!=""){
$neworder["{$notmovedkey}"] = $array["{$notmovedkey}"];
}
$int++;
}
return($neworder);
}
This is not too elegant but it works.
//this is a function to move items in an array up or down
//in the array. it is done by breaking the array into two
//separate arrays and then have a loop creates the final array
//adding the item we want to move when the counter is equal
//to the new position we established
//the array key, position and direction were passed via a query string
//parameters
//$array- the array you are modifying
//$keytomove - the key of the item you wish to move
//$pos - the current position of the item: used a count($array) function
//and then loop with incrementing integer to add the position to the up //or down button
//$dir - the direction you want to move it - "up"/"dn"
function change_pos($array, $keytomove, $pos, $dir){
//count the original number of rows
$count = count($array);
//set the integer we will use to place the moved item
if($dir=="up"){
if($pos==1){
//if the item is already first and we try moving it up
//we send it to the end of the array
$change = $count;
}else{
//anywhere else it just moves back one closer to the start of the array
$change = $pos-1;
}
}
//do the same for the down button
if($dir=="dn"){
if($pos==$count){
$change = 1;
}else{
$change = $pos+1;
}
}
//copy the element that you wish to move
$move = $array[$keytomove];
//delete the original from the main array
unset($array[$keytomove]);
//create an array of the names of the values we
//are not moving
$preint = 1;
foreach($array as $c){
$notmoved["{$preint}"] = $c['name'];
$preint++;
}
//loop through all the elements
$int = 1;
while($int<=$count){
//dynamically change the key of the unmoved item as we increment the counter
$notmovedkey = $notmoved["$int"];
//when the counter is equal to the position we want
//to place the moved entry we pump it into a new array
if($int==$change){
$neworder["{$keytomove}"] = $move;
}
//add all the other array items if the position number is not met and
//resume adding them once the moved item is written
if($contkey!=""){
$neworder["{$contkey}"] = $array["{$contkey}"];
}
$int++;
}
return($neworder);
}
This is not too elegant but it works.
Take note that end() does not recursively set your multiple dimension arrays' pointer to the end.
Take a look at the following:
<?php
// create the array for testing
$a = array();
$i = 0;
while($i++ < 3){
$a[] = array(dechex(crc32(mt_rand())),dechex(crc32('lol'.mt_rand())));
}
// show the array tree
echo '<pre>';var_dump($a);
// set the pointer of $a to the end
end($a);
// get the current element of $a
var_dump(current($a));
// get the current element of the current element of $a
var_dump(current(current($a)));
?>
You will notice that you probably get something like this:
array(3) {
[0]=>
array(2) {
[0]=>
string(8) "764d8d20"
[1]=>
string(8) "85ee186d"
}
[1]=>
array(2) {
[0]=>
string(8) "c8c72466"
[1]=>
string(8) "a0fdccb2"
}
[2]=>
array(2) {
[0]=>
string(8) "3463a31b"
[1]=>
string(8) "589f6b63"
}
}
array(2) {
[0]=>
string(8) "3463a31b"
[1]=>
string(8) "589f6b63"
}
string(8) "3463a31b"
The array elements' pointer are still at the first one as current. So do take note.
This is simple way how to get file extension.
<?php
$filename = 'somefile.jpg';
echo end(explode(".", $filename)); // return jpg string
$filename = 'the_another_file.html';
echo end(explode(".", $filename)); // return html string
?>
RE: mika dot stenberg at helsinki dot fi
Your function array_set_current is flawed:
function array_set_current(&$array, $key){
reset($array);
while(current($array)){
if(key($array) == $key){
break;
}
next($array);
}
}
Notice that current() cannot distinguish the end of an array from a boolean FALSE element value. For example, try this:
$array = array(false, 'This', 'is', 'a', 'test');
array_set_current($array, 3);
var_dump(current($array));
This will work:
function array_set_current(&$array, $key) {
reset($array);
foreach ($array as $value) {
if (key($array) === $key) {
break;
}
}
}
Also, I prefer key($array) === $key over key($array) == $key.
Posted by johnny at west dot net
03-Nov-2006 06:45
>> An easier way to get the last key:
>> $lastkey = end(array_keys($arr));
As stated in a previous note, this may not function as expected (or at all) as end() takes the parameter by reference and you cannot pass a function call by reference.
An easier way to get the last key:
$lastkey = end(array_keys($arr));
This function returns the value at the end of the array, but you may sometimes be interested in the key at the end of the array, particularly when working with non integer indexed arrays:
<?php
// Returns the key at the end of the array
function endKey($array){
end($array);
return key($array);
}
?>
Usage example:
<?php
$a = array("one" => "apple", "two" => "orange", "three" => "pear");
echo endKey($a); // will output "three"
?>
In some previous post you can use
current($array)
instead of
$array[key($array)]
I think it's more self-explaining.
Please note that from version 5.0.4 ==> 5.0.5 that this function now takes an array. This will possibly break some code for instance:
<?php
echo ">> ".end(array_keys(array('x' => 'y')))."\n";
?>
which will return "Fatal error: Only variables can be passed by reference" in version <= 5.0.4 but not in 5.0.5.
If you run into this problem with nested function calls, then an easy workaround is to assign the result from array_keys (or whatever function) to an intermediary variable:
<?php
$x = array_keys(array('x' => 'y'));
echo ">> ".end($x)."\n";
?>
Here's something useful with arrays that I did: change an items position up or down in array. Thanks to previous posters for some useful functions (included):
// $mode -1 (negat) moves the item down, +1 (pos) moves the item up
// I used this because i parsed the mode from the query string
// You get the picture though
// $from_id points which item to move
function change_pos($array, $from_id, $mode){
// get hold of the beginning and the end
$start = first($array);
$end = last($array);
reset($array);
// find the position in an array
array_set_current($array, $from_id);
// remember the old value
$temp = $archive[ $from_id ];
// move down
if ($uusi_id < 0){
if (key($array) != $end) {
$array[ $from_id ] = next($array);
$array[key($aray)] = $temp;
}
else echo "Couldnt move it!";
}
// move up
else if ( key($array) != $start ) {
$array[ $from_id ] = prev($array);
$array[key($array)] = $temp;
save($array);
}
else echo "Couldnt do it !";
}
function array_set_current(&$array, $key){
reset($array);
while(current($array)){
if(key($array) == $key){
break;
}
next($array);
}
}
function first(&$array) {
if (!is_array($array)) return null;
if (!count($array)) return null;
reset($array);
return key($array);
}
function last(&$array) {
if (!is_array($array)) return null;
if (!count($array)) return null;
end($array);
return key($array);
}
Fix for unknown writer of 29-aug-2002.
If you need to get a reference to the first or last element of an array, use these functions:
function &first(&$array) {
if (!is_array($array))
return null;
if (!count($array))
return false; // like reset()
reset($array);
return $array[key($array)];
}
function &last(&$array) {
if (!is_array($array))
return null;
if (!count($array))
return false; // like end()
end($array);
return $array[key($array)];
}
Example (watch out - use as &last() and &first()):
$a = array( 0 => 'less', 10 => 'ten', 20 => ' more');
if ($first = & first($a)) // not false or null
$first = 'nothing';
if ($last = & last($a)) // not false or null
$last = 'double';
Now $a is array( 0 => 'nothing', 10 => 'ten', 20 => ' double')
If you need to get a reference on the first or last element of an array, use these functions because reset() and end() only return you a copy that you cannot dereference directly:
function first(&$array) {
if (!is_array($array)) return &$array;
if (!count($array)) return null;
reset($array);
return &$array[key($array)];
}
function last(&$array) {
if (!is_array($array)) return &$array;
if (!count($array)) return null;
end($array);
return &$array[key($array)];
}
When adding an element to an array, it may be interesting to know with which key it was added. Just adding an element does not change the current position in the array, so calling key() won't return the correct key value; you must first position at end() of the array:
function array_add(&$array, $value) {
$array[] = $value; // add an element
end($array); // important!
return key($array);
}
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