how to force foreach reset in php - php

Is possible in php to reset The foreach?
for example:
foreach($rows as $row)
{
if(something true)
{
continue foreach;
}
else
{
break;
reset foreach;//I mean start foreach again...
}
}
----------------------------------Edited
Thanks my friend for your answers...
The condition generate from result of foreach so I can not use function.
I wana sortet it by (fro example) alphabet...in many DIV html.
I can not filter result by SQL for same reson.
So mybe I have to use a css trick.

You could do something around these lines (and avoid the limitations of recursion):
while (True) {
$reset = False;
foreach ($rows as $row) {
if(something true) {
continue;
} else {
$reset = True;
break;
}
}
if ( ! $reset ) {
break; # break out of the while(true)
}
# otherwise the foreach loop is `reset`
}

It seems that reset inside a foreach has no effect.
You can implement this if you make your own Traversable.

Try using reset/while/each which is functionally equivalent to foreach according to the manual then you can use reset within the loop like so:
<?php
$arr = array(1=>'one',2=>'two',3=>'three');
reset($arr);
$resets=0;
while (list($key, $value) = each($arr))
{
echo "$key => $value<br />\n";
if($value=='three')
{
if($resets==0){$resets++;echo "==Resetting==<br />\n";reset($arr);continue;}
}
}
Output:
1 => one
2 => two
3 => three
==Resetting==
1 => one
2 => two
3 => three
As pointed out by Mike Kormendy in the comments, each is deprecated as of php 7.2.
If for some reason you like my approach, you can emulate each using a combination of key(), current(), and next() like so:
<?php
$arr = array(1=>'one',2=>'two',3=>'three');
reset($arr);
$resets=0;
while ( list($key,$value) = [key($arr),current($arr)] )
{
if($key === NULL){ break; }
next($arr);
echo "$key => $value<br />\n";
if($value=='three')
{
if($resets==0){$resets++;echo "==Resetting==<br />\n";reset($arr);continue;}
}
}
Output:
1 => one
2 => two
3 => three
==Resetting==
1 => one
2 => two
3 => three
This answer was posted many years ago.
Going forward, I'd avoid this type of approach like the plague.
The accepted answer is a lot more elegant.

I think you can do that by putting the for each in a function and then calling the function from itself.
function doForEach($rows) {
foreach($rows as $row)
{
if(something true)
{
continue foreach;
}
else
{
break;
doForEach($rows);
}
}
}
Be very careful with this however, you'll likely end up in a loop.

Why reset the foreach ? If you really need this... But care about infinite loop !
function myForeach($array){
foreachforeach($rows as $row){
if(something true){
continue foreach;
}else{
myForeach($array);
}

Yes it is possible to reset a foreach but not the way you described it in your question. You can read my approaches below.
--------- Implement Iterator --------------------------------
Implement the Iterator interface.
Link: http://nl1.php.net/manual/en/class.iterator.php.
Code example:
class myIterator implements Iterator {
private $maxIterations = 2; // the maxumum amount of iterations
private $currentIteration = 1; // the current iteration number
private $lastKey = null;
private $lastValue = null;
private $currentValue = null;
private $position = 0;
private $array;
public function __construct($array) {
$this->array = $array;
end($array);
$this->lastKey = key($array);
$this->lastValue = current($array);
}
public function rewind() {
$this->position = 0;
reset($this->array);
}
public function valid() {
// Reset when there are no elements
if($this->position > $this->lastKey &&
$this->currentValue === $this->lastValue &&
$this->currentIteration < $this->maxIterations){
$this->rewind();
++$this->currentIteration;
}
$isSet = isset($this->array[$this->position]);
return $isSet;
}
public function current() {
$this->currentValue = $this->array[$this->position];
return $this->currentValue;
}
public function key() {
return $this->position;
}
public function next() {
++$this->position;
}
}
$array = array("A",
"B",
"C",
);
$it = new myIterator($array);
// the iterator will traverse the array twice
foreach($it as $key => $value) {
echo 'key : ' . $key . '<br>';
echo 'val : ' . $value . '<br>';
echo '<br>';
}
The output
key : 0
val : A
key : 1
val : B
key : 2
val : C
key : 0
val : A
key : 1
val : B
key : 2
val : C
--------- InfiniteIterator + LimitIterator --------------------------------
You can use InfiniteIterator in combination with LimitIterator.
$obj = new stdClass();
$obj->Mon = "Monday";
$obj->Tue = "Tuesday";
$obj->Wed = "Wednesday";
$obj->Thu = "Thursday";
$obj->Fri = "Friday";
$obj->Sat = "Saturday";
$obj->Sun = "Sunday";
$infinate = new InfiniteIterator(new ArrayIterator($obj));
foreach ( new LimitIterator($infinate, 0, 14) as $value ) {
print($value . PHP_EOL);
}
// OUTPUT:
Monday
Tuesday
Wednesday
Thursday
Friday
Saturday
Sunday
Monday
Tuesday
Wednesday
Thursday
Friday
Saturday
Sunday
See link: http://php.net/manual/en/class.infiniteiterator.php
--------- ArrayObject + ArrayIterator --------------------------------
According to the PHP manual it should also be possible to achieve it by using ArrayIterator.
When you want to iterate over the same array multiple times you need
to instantiate ArrayObject and let it create ArrayIterator instances
that refer to it either by using foreach or by calling its
getIterator() method manually.
Their description is not clear to me, but it think that they mean something like this.
$array = array('honda', 'toyota', 'suzuki', 'mazda', 'nissan');
end($array);
$lastKey = key($array);
$maxIterations = 2;
$currentIteration = 1;
$arrayObj = new ArrayObject($array);
for($iterator = $arrayObj->getIterator(); $iterator->valid(); $iterator->next()){
echo $iterator->key() . ' : ' . $iterator->current() . '<br>';
if( $iterator->key() === $lastKey &&
$currentIteration < $maxIterations ){
$iterator->rewind();
++$currentIteration;
echo $iterator->key() . ' : ' . $iterator->current() . '<br>';
}
}
OUTPUT:
0 : honda
1 : toyota
2 : suzuki
3 : mazda
4 : nissan
0 : honda
1 : toyota
2 : suzuki
3 : mazda
4 : nissan
Link: http://php.net/manual/en/class.arrayiterator.php

You can reset the foreach with: "using it in this below as well"
$value = "";
Or restart by pointing where to go after the end:
a:
"as restarting"
goto a;
So in the code from the asker in this post do like this:
a:
foreach($rows as $row){
$value++;
if(something true){
continue foreach;
}
else {
break;
$value = ""; // A value reset
goto a; //I mean start foreach again...
}
$value = ""; //perhaps a value reset here?
}

Related

How to get the values only if all the keys have matched?

I want to make a method that returns keys and values. But only if the keys include the following string "_1" and "__last".
If only one matches then exit the function, only if the two string are included in the key, return the key with the value for a weather.
$infoList = array("_key_1"=>array("time"=>9, "day"=>"Tuesday", "weather"=>"sunny",
"humidity"=>"80%"),
"_key_2"=>array("time"=>5, "day"=>"Tuesday", "weather"=>"cloudy"),
"_key__last"=>array("time"=>3, "day"=>"Sunday", "weather"=>"rainy"))
public function getData() {
$list = array();
foreach($infoList as $key){
if(preg_match('/(_key)_(_1)/', $key) && preg_match('/(_key)_(__last)/', $key) == TRUE){
$list[$key] = $list[$key]["weather"]
}
}
return $list
}
You are making your life so much more difficult that it need be, use str_contains() its easier than building complex REGEX's and getting very confused by the look of it :)
I also fixed a number of other mistakes, such as the foreach that was not going to work, so check all the code.
It is also better to pass data to a function/method otherwise you get into scoping issues!
$infoList = array("_key_1"=>array("time"=>9, "day"=>"Tuesday", "weather"=>"sunny", "humidity"=>"80%"),
"_key_2"=>array("time"=>5, "day"=>"Tuesday", "weather"=>"cloudy"),
"_key__last"=>array("time"=>3, "day"=>"Sunday", "weather"=>"rainy"));
function getData(Array $infoList) {
$list = [];
$found = 0;
foreach($infoList as $key => $val) {
if( str_contains($key, '_1') || str_contains($key, '__last') ) {
$list[$key] = $val["weather"];
$found++;
}
}
if ( $found >= 2 ) {
return $list;
} else {
return false;
}
}
$res = getData($infoList);
if ( $res !== false ){
print_r($res);
} else {
echo 'Not Found';
}
RESULTS
Array
(
[_key_1] => sunny
[_key__last] => rainy
)
If you want to stick with RegEx, you can use positive lookaheads, the same way you check for passwords characters :
<?php
$pattern = '/^(?=.*_1)(?=.*_last).*$/';
$shouldMatch = [
'_1_last',
'foo_1bar_lasthello',
'_last_1',
'foo_lastbar_1hello'
];
echo 'next ones should match : ' . PHP_EOL;
foreach ($shouldMatch as $item)
{
if (preg_match($pattern, $item))
echo $item . PHP_EOL;
}
$shouldNOTMatch = [
'_2_first',
'bar_lasthello',
'foo_las_1hello'
];
echo 'next ones should NOT match : ' . PHP_EOL;
foreach ($shouldNOTMatch as $item)
{
// v------------ check
if (!preg_match($pattern, $item))
echo $item . PHP_EOL;
}
Output :
next ones should match :
_1_last
foo_1bar_lasthello
_last_1
foo_lastbar_1hello
next ones should NOT match :
_2_first
bar_lasthello
foo_las_1hello

Sorting PHP array without ksort

I am trying to manually sort a PHP array without making use of ksort.
This is how my code looks at the moment:
function my_ksort(&$arg){
foreach($arg as $key1 => $value1){
foreach($arg as $key2 => $value2){
if($key1 > $key2){
$aux = $value2;
$arg[$key2] = $value1;
$arg[$key1] = $aux;
}
}
}
}
It doesn't sort, I can't figure out how to make it sort.
You could try this:
function my_ksort(&$arg)
{
$keys=array_keys($arg);
sort($keys);
foreach($keys as $key)
{
$val=$arg[$key];
unset($arg[$key]);
$arg[$key]=$val;
}
}
I'm sorting the keys separately and then deleting the elements one-by-one and appending them to the end, in ascending order.
I'm using another sorting function (sort()), but if you want to eliminate all available sorting functions from your emulation, sort() is much easier to emulate. In fact, #crypticous's algorithm does just that!
This function return array in ASC. Take in consideration that I'm using goto which is supported in (PHP 5 >= 5.3.0)
function ascending_array($array){
if (!is_array($array)){
$array = explode(",", $array);
}
$new = array();
$flag = true;
iter:
$array = array_values($array); // recount array values with new offsets
(isset($min["max"])) ? $min["value"] = $min["max"] : $min["value"] = $array[0];
$min["offset"] = 0;
for ($i=0;$i<count($array);$i++){
if ($array[$i] < $min["value"]){ // redefine min values each time if statement executed
$min["value"] = $array[$i];
$min["offset"] = $i;
}
if ($flag){ // execute only first time
if ($array[$i] > $min["value"]){ // define max value from array
$min["max"] = $array[$i];
}
$flag = false;
}
if ($i === (count($array)-1)){ // last array element
array_push($new,$min["value"]);
unset($array[$min["offset"]]);
}
}
if (count($array)!=0){
goto iter;
}
print_r($new);
}
$arr = array(50,25,98,45);
ascending_array($arr); // 25 45 50 98
PS. When I was studying php, I wrote this function and now remembered that I had it (that's why I really don't remember what I am doing in it, though fact is it's working properly and hopefully there are comments too), hope you'll enjoy :)
DEMO
I was checking some issue related to this post and i wanted to give my insight about it ! here's what i would have done to implement php's sort :
$array_res = array();
$array = array(50,25,98,45);
$i=0;
$temp = $array[0];
$key = array_search($temp, $array);
while ($i<count($array)-1){
$temp = $array[0];
for($n=0;$n<count($array) ;$n++)
{
if($array[$n]< $temp && $array[$n] != -1 )
{
$temp = $array[$n];
}
else{continue;}
}
//get the index for later deletion
$key = array_search($temp, $array);
array_push($array_res, $temp);
/// flag on those which were ordered
$array[$key] =-1;
$i++;
}
// lastly append the highest number
for($n=0;$n<count($array) ;$n++)
{
if ($array[$n] != -1)
array_push($array_res, $array[$n]);
}
// display the results
print_r($array_res);
This code will display : Array
(
[0] => 25
[1] => 45
[2] => 50
[3] => 98
)
Short and sweet
function custom_ksort($arg)
{
$keys = array_keys($arg);
sort($keys);
foreach($keys as $newV)
{
$newArr[$newV] = $arg[$newV];
}
return $newArr;
}
It looks like your issue is that you're changing "temporary" characters $key1 and $key2 but not the actual arrays. You have to change $arg, not just $key1 and $key2.
Try something like:
$arr = Array(3=>"a",7=>"b");
print_r( $arr );
foreach( $arr as $k=>$v ){
unset($arr[$k]);
$arr[$k+1] = $v;
}
print_r($arr);

Giving text labels to integer ranges in PHP

I am attempting to take simple number ranges (in the example of this project, I am working with different increments of money for each user. FAKE money, by the way...) and group them into classes that can be displayed publicly instead of the absolute number.
Here is a rough sample of code for the long way to write this function as an example:
<?
$money=500001;
if($money > 0 AND $money < 5000) {
$class = 'Poor';
} elseif ($money >= 5000 AND $money < 25000) {
$class = 'Lower Class';
} elseif ($money >= 25000 AND $money < 100000) {
$class = 'Middle Class';
} elseif ($money >= 100000) {
$class = 'Upper Class';
}
echo $class;
exit();
?>
Now, I know this function will work, but it seems like an absolutely awful way in going about writing it, since if more $class' are added, it becomes far too long.
Now my question is: Is there a shorter way to write this? Possibly using range() and/or an array of values?
I would go for something like this:
function getClass($sal){
$classes = array(5000=>"poor", 25000=>"Lower Class", 100000=>"Middle Class");
foreach ($classes as $key => $value) {
if($sal < $key){
return $value;
}
}
return "Upper Class";
}
$salary = 90000;
$sal_class = getClass($salary);
echo "salary class = $sal_class\n";
Output:
sal = Middle Class
A bit similar to above answer, but a better one. I will suggest using OO approach.
Class Foo {
protected $class = array(
array("poor", 0, 5000),
array("medium", 5000, 25000)
);
function get_class($amount) {
foreach ($this -> class as $key => $value) {
if($amount > $value[1] && $amount < $value[2]) {
return $value[0];
}
}
return null;
}
function add_class(array $arr) {
$this -> class[] = $arr;
}
}
Usage:
$obj = new Foo();
$obj -> get_class(6000); //Outputs: medium
$obj -> add_class(array("rich", 25000, 50000)); //Add a new class
$obj -> get_class(35000); //Outputs: rich

How to skip the 1st key in an array loop?

I have the following code:
if ($_POST['submit'] == "Next") {
foreach($_POST['info'] as $key => $value) {
echo $value;
}
}
How do I get the foreach function to start from the 2nd key in the array?
For reasonably small arrays, use array_slice to create a second one:
foreach(array_slice($_POST['info'],1) as $key=>$value)
{
echo $value;
}
foreach(array_slice($_POST['info'], 1) as $key=>$value) {
echo $value;
}
Alternatively if you don't want to copy the array you could just do:
$isFirst = true;
foreach($_POST['info'] as $key=>$value) {
if ($isFirst) {
$isFirst = false;
continue;
}
echo $value;
}
Couldn't you just unset the array...
So if I had an array where I didn't want the first instance,
I could just:
unset($array[0]);
and that would remove the instance from the array.
If you were working with a normal array, I'd say to use something like
foreach (array_slice($ome_array, 1) as $k => $v {...
but, since you're looking at a user request, you don't have any real guarantees on the order in which the arguments might be returned - some browser/proxy might change its behavior or you might simply decide to modify your form in the future. Either way, it's in your best interest to ignore the ordering of the array and treat POST values as an unordered hash map, leaving you with two options :
copy the array and unset the key you want to ignore
loop through the whole array and continue when seeing the key you wish to ignore
in loop:
if ($key == 0) //or whatever
continue;
Alternative way is to use array pointers:
reset($_POST['info']); //set pointer to zero
while ($value=next($_POST['info']) //ponter+1, return value
{
echo key($_POST['info']).":".$value."\n";
}
If you're willing to throw the first element away, you can use array_shift(). However, this is slow on a huge array. A faster operation would be
reset($a);
unset(key($a));
On a array filled with 1000 elements the difference is quite minimal.
Test:
<?php
function slice($a)
{
foreach(array_slice($a, 1) as $key)
{
}
return true;
}
function skip($a)
{
$first = false;
foreach($a as $key)
{
if($first)
{
$first = false;
continue;
}
}
return true;
}
$array = array_fill(0, 1000, 'test');
$t1 = time() + microtime(true);
for ($i = 0; $i < 1000; $i++)
{
slice($array);
}
var_dump((time() + microtime(true)) - $t1);
echo '<hr />';
$t2 = time() + microtime(true);
for ($i = 0; $i < 1000; $i++)
{
skip($array);
}
var_dump((time() + microtime(true)) - $t2);
?>
Output:
float(0.23605012893677)
float(0.24102783203125)
Working Code From My Website For Skipping The First Result and Then Continue.
<?php
$counter = 0;
foreach ($categoriest as $category) { if ($counter++ == 0) continue; ?>
It is working on opencart also in tpl file do like this in case you need.
foreach($_POST['info'] as $key=>$value) {
if ($key == 0) { //or what ever the first key you're using is
continue;
} else {
echo $value;
}
}
if you structure your form differently
<input type='text' name='quiz[first]' value=""/>
<input type='text' name='quiz[second]' value=""/>
...then in your PHP
if( isset($_POST['quiz']) AND
is_array($_POST['quiz'])) {
//...and we'll skip $_POST['quiz']['first']
foreach($_POST['quiz'] as $key => $val){
if($key == "first") continue;
print $val;
}
}
...you can now just loop over that particular structure and access rest normally
How about something like this? Read off the first key and value using key() and current(), then array_shift() to dequeue the front element from the array (EDIT: Don't use array_shift(), it renumbers any numerical indices in the array, which you don't always want!).
<?php
$arr = array(
'one' => "ONE!!",
'two' => "TWO!!",
'three' => "TREE",
4 => "Fourth element",
99 => "We skipped a few here.."
) ;
$firstKey = key( $arr ) ;
$firstVal = current( $arr ) ;
echo( "OK, first values are $firstKey, $firstVal" ) ;
####array_shift( $arr ) ; #'dequeue' front element # BAD! renumbers!
unset( $arr[ $firstKey ] ) ; # BETTER!
echo( "Now for the rest of them" ) ;
foreach( $arr as $key=>$val )
{
echo( "$key => $val" ) ;
}
?>

Find the last element of an array while using a foreach loop in PHP

I am writing a SQL query creator using some parameters. In Java, it's very easy to detect the last element of an array from inside the for loop by just checking the current array position with the array length.
for(int i=0; i< arr.length;i++){
boolean isLastElem = i== (arr.length -1) ? true : false;
}
In PHP they have non-integer indexes to access arrays. So you must iterate over an array using a foreach loop. This becomes problematic when you need to take some decision (in my case to append or/and parameter while building query).
I am sure there must be some standard way of doing this.
How do you solve this in PHP?
It sounds like you want something like this:
$numItems = count($arr);
$i = 0;
foreach($arr as $key=>$value) {
if(++$i === $numItems) {
echo "last index!";
}
}
That being said, you don't -have- to iterate over an "array" using foreach in php.
You could get the value of the last key of the array using end(array_keys($array)) and compare it to the current key:
$last_key = end(array_keys($array));
foreach ($array as $key => $value) {
if ($key == $last_key) {
// last element
} else {
// not last element
}
}
Note: This doesn't work because calling next() advances the array pointer, so you're skipping every other element in the loop
why so complicated?
foreach($input as $key => $value) {
$ret .= "$value";
if (next($input)==true) $ret .= ",";
}
This will add a , behind every value except the last one!
When toEnd reaches 0 it means it is at the last iteration of the loop.
$toEnd = count($arr);
foreach($arr as $key=>$value) {
if (0 === --$toEnd) {
echo "last index! $value";
}
}
The last value is still available after the loop, so if you just want to use it for more stuff after the loop this is better:
foreach($arr as $key=>$value) {
//something
}
echo "last index! $key => $value";
If you do not want to treat the last value as special inside loops. This should be faster if you have large arrays. (If you reuse the array after the loop inside the same scope you have to "copy" the array first).
//If you use this in a large global code without namespaces or functions then you can copy the array like this:
//$array = $originalArrayName; //uncomment to copy an array you may use after this loop
//end($array); $lastKey = key($array); //uncomment if you use the keys
$lastValue = array_pop($array);
//do something special with the last value here before you process all the others?
echo "Last is $lastValue", "\n";
foreach ($array as $key => $value) {
//do something with all values before the last value
echo "All except last value: $value", "\n";
}
//do something special with the last value here after you process all the others?
echo "Last is $lastValue", "\n";
And to answer your original question "in my case to append or/and parameter while building query"; this will loop over all the values, then join them together to a string with " and " between them but not before the first value or after the last value:
$params = [];
foreach ($array as $value) {
$params[] = doSomething($value);
}
$parameters = implode(" and ", $params);
There are already many answers, but it's worth to look into iterators as well, especially as it has been asked for a standard way:
$arr = range(1, 3);
$it = new CachingIterator(new ArrayIterator($arr));
foreach($it as $key => $value)
{
if (!$it->hasNext()) echo 'Last:';
echo $value, "\n";
}
You might find something that does work more flexible for other cases, too.
One way could be to detect if the iterator has next. If there is no next attached to the iterator it means you are in the last loop.
foreach ($some_array as $element) {
if(!next($some_array)) {
// This is the last $element
}
}
SINCE PHP 7.3 :
You could get the value of the last key of the array using array_key_last($array) and compare it to the current key:
$last_key = array_key_last($array);
foreach ($array as $key => $value) {
if ($key == $last_key) {
// last element
} else {
// not last element
}
}
to get first and last element from foreach array
foreach($array as $value) {
if ($value === reset($array)) {
echo 'FIRST ELEMENT!';
}
if ($value === end($array)) {
echo 'LAST ITEM!';
}
}
So, if your array has unique array values, then determining last iteration is trivial:
foreach($array as $element) {
if ($element === end($array))
echo 'LAST ELEMENT!';
}
As you see, this works if last element is appearing just once in array, otherwise you get a false alarm. In it is not, you have to compare the keys (which are unique for sure).
foreach($array as $key => $element) {
end($array);
if ($key === key($array))
echo 'LAST ELEMENT!';
}
Also note the strict coparision operator, which is quite important in this case.
Don't add a comma after the last value:
The array:
$data = ['lorem', 'ipsum', 'dolor', 'sit', 'amet'];
The function:
$result = "";
foreach($data as $value) {
$resut .= (next($data)) ? "$value, " : $value;
}
The result:
print $result;
lorem, ipsum, dolor, sit, amet
You can still use that method with associative arrays:
$keys = array_keys($array);
for ($i = 0, $l = count($array); $i < $l; ++$i) {
$key = $array[$i];
$value = $array[$key];
$isLastItem = ($i == ($l - 1));
// do stuff
}
// or this way...
$i = 0;
$l = count($array);
foreach ($array as $key => $value) {
$isLastItem = ($i == ($l - 1));
// do stuff
++$i;
}
Assuming you have the array stored in a variable...
foreach($array as $key=>$value)
{
echo $value;
if($key != count($array)-1) { echo ", "; }
}
If you need to do something for every element except either the first or the last and only if there is more than one element in the array, I prefer the following solution.
I know there are many solutions above and posted months/one year before mine, but this is something I feel is fairly elegant in its own right. The check every loop is also a boolean check as opposed to a numeric "i=(count-1)" check, which may allow for less overhead.
The structure of the loop may feel awkward, but you can compare it to the ordering of thead (beginning), tfoot (end), tbody (current) in HTML table tags.
$first = true;
foreach($array as $key => $value) {
if ($first) {
$first = false;
// Do what you want to do before the first element
echo "List of key, value pairs:\n";
} else {
// Do what you want to do at the end of every element
// except the last, assuming the list has more than one element
echo "\n";
}
// Do what you want to do for the current element
echo $key . ' => ' . $value;
}
For instance, in web development terms, if you want to add a border-bottom to every element except the last in an unordered list (ul), then you can instead add a border-top to every element except the first (the CSS :first-child, supported by IE7+ and Firefox/Webkit supports this logic, whereas :last-child is not supported by IE7).
You can feel free to reuse the $first variable for each and every nested loop as well and things will work just fine since every loop makes $first false during the first process of the first iteration (so breaks/exceptions won't cause issues).
$first = true;
foreach($array as $key => $subArray) {
if ($first) {
$string = "List of key => value array pairs:\n";
$first = false;
} else {
echo "\n";
}
$string .= $key . '=>(';
$first = true;
foreach($subArray as $key => $value) {
if ($first) {
$first = false;
} else {
$string .= ', ';
}
$string .= $key . '=>' . $value;
}
$string .= ')';
}
echo $string;
Example output:
List of key => value array pairs:
key1=>(v1_key1=>v1_val1, v1_key2=>v1_val2)
key2=>(v2_key1=>v2_val1, v2_key2=>v2_val2, v2_key3=>v2_val3)
key3=>(v3_key1=>v3_val1)
This should be the easy way to find the last element:
foreach ( $array as $key => $a ) {
if ( end( array_keys( $array ) ) == $key ) {
echo "Last element";
} else {
echo "Just another element";
}
}
Reference : Link
I have a strong feeling that at the root of this "XY problem" the OP wanted just implode() function.
As your intention of finding the EOF array is just for the glue. Get introduced to the below tactic. You need not require the EOF:
$given_array = array('column1'=>'value1',
'column2'=>'value2',
'column3'=>'value3');
$glue = '';
foreach($given_array as $column_name=>$value){
$where .= " $glue $column_name = $value"; //appending the glue
$glue = 'AND';
}
echo $where;
o/p:
column1 = value1 AND column2 = value2 AND column3 = value3
How about using "end"?
http://php.net/manual/en/function.end.php
It sounds like you want something like this:
$array = array(
'First',
'Second',
'Third',
'Last'
);
foreach($array as $key => $value)
{
if(end($array) === $value)
{
echo "last index!" . $value;
}
}
$array = array("dog", "rabbit", "horse", "rat", "cat");
foreach($array as $index => $animal) {
if ($index === array_key_first($array))
echo $animal; // output: dog
if ($index === array_key_last($array))
echo $animal; // output: cat
}
you can do a count().
for ($i=0;$i<count(arr);$i++){
$i == count(arr)-1 ? true : false;
}
or if you're looking for ONLY the last element, you can use end().
end(arr);
returns only the last element.
and, as it turns out, you CAN index php arrays by integers. It's perfectly happy with
arr[1];
You could also do something like this:
end( $elements );
$endKey = key($elements);
foreach ($elements as $key => $value)
{
if ($key == $endKey) // -- this is the last item
{
// do something
}
// more code
}
I kinda like the following as I feel it is fairly neat. Let's assume we're creating a string with separators between all the elements: e.g. a,b,c
$first = true;
foreach ( $items as $item ) {
$str = ($first)?$first=false:", ".$item;
}
Here's my solution:
Simply get the count of your array, minus 1 (since they start in 0).
$lastkey = count($array) - 1;
foreach($array as $k=>$a){
if($k==$lastkey){
/*do something*/
}
}
foreach ($array as $key => $value) {
$class = ( $key !== count( $array ) -1 ) ? " class='not-last'" : " class='last'";
echo "<div{$class}>";
echo "$value['the_title']";
echo "</div>";
}
Reference
If it is a single dimensional array you can do this to keep it short and sweet:
foreach($items as $idx => $item) {
if (!isset($items[$idx+1])) {
print "I am last";
}
}
Here's another way you could do it:
$arr = range(1, 10);
$end = end($arr);
reset($arr);
while( list($k, $v) = each($arr) )
{
if( $n == $end )
{
echo 'last!';
}
else
{
echo sprintf('%s ', $v);
}
}
If I understand you, then all you need is to reverse the array and get the last element by a pop command:
$rev_array = array_reverse($array);
echo array_pop($rev_array);
You could also try this to make your query... shown here with INSERT
<?php
$week=array('one'=>'monday','two'=>'tuesday','three'=>'wednesday','four'=>'thursday','five'=>'friday','six'=>'saturday','seven'=>'sunday');
$keys = array_keys($week);
$string = "INSERT INTO my_table ('";
$string .= implode("','", $keys);
$string .= "') VALUES ('";
$string .= implode("','", $week);
$string .= "');";
echo $string;
?>
For SQL query generating scripts, or anything that does a different action for the first or last elements, it is much faster (almost twice as fast) to avoid using unneccessary variable checks.
The current accepted solution uses a loop and a check within the loop that will be made every_single_iteration, the correct (fast) way to do this is the following :
$numItems = count($arr);
$i=0;
$firstitem=$arr[0];
$i++;
while($i<$numItems-1){
$some_item=$arr[$i];
$i++;
}
$last_item=$arr[$i];
$i++;
A little homemade benchmark showed the following:
test1: 100000 runs of model morg
time: 1869.3430423737 milliseconds
test2: 100000 runs of model if last
time: 3235.6359958649 milliseconds
Another way to go is to remember the previous loop cycle result and use that as the end result:
$result = $where = "";
foreach ($conditions as $col => $val) {
$result = $where .= $this->getAdapter()->quoteInto($col.' = ?', $val);
$where .= " AND ";
}
return $this->delete($result);

Categories