How do I get the current index in a foreach loop?
foreach ($arr as $key => $val)
{
// How do I get the index?
// How do I get the first element in an associative array?
}
10 Answers
In your sample code, it would just be $key.
If you want to know, for example, if this is the first, second, or ith iteration of the loop, this is your only option:
$i = -1;
foreach($arr as $val) {
$i++;
//$i is now the index. if $i == 0, then this is the first element.
...
}
Of course, this doesn't mean that $val == $arr[$i] because the array could be an associative array.
2 Comments
pbarney
Maybe start with
$i = 0; and move your $i++;incrementor to the bottom of the loop for better readability.
Kip
@pbarney I disagree. Doing the increment at the end is a bug waiting to happen: if there is any
continue; statement in the loop body, or anyone might reasonably add one in the future, an increment at the end doesn't work. Also, this keeps the declaration of the variable and the increment close together.This is the most exhaustive answer so far and gets rid of the need for a $i variable floating around. It is a combo of Kip and Gnarf's answers.
$array = array( 'cat' => 'meow', 'dog' => 'woof', 'cow' => 'moo', 'computer' => 'beep' );
foreach( array_keys( $array ) as $index=>$key ) {
// display the current index + key + value
echo $index . ':' . $key . $array[$key];
// first index
if ( $index == 0 ) {
echo ' -- This is the first element in the associative array';
}
// last index
if ( $index == count( $array ) - 1 ) {
echo ' -- This is the last element in the associative array';
}
echo '<br>';
}
Hope it helps someone.
foreach($array as $key=>$value) {
// do stuff
}
$key is the index of each $array element
3 Comments
Andrew Cavanagh
Not neessarily. If your array looks like this: ` $array = array( 'cat' => 'meow', 'dog' => 'woof', 'cow' => 'moo', 'computer' => 'beep' );` the the $key of the first item would be 'cat'.
Xman Classical
Thanks for your response. I think the index will be the key. Here are: 'cat', 'dog', ...
Syed Priom
I don't understand why this is not the best answer on this page.
$i = 0;
foreach ($arr as $key => $val) {
if ($i === 0) {
// first index
}
// current index is $i
$i++;
}
Comments
The current index is the value of $key. And for the other question, you can also use:
current($arr)
to get the first element of any array, assuming that you aren't using the next(), prev() or other functions to change the internal pointer of the array.
1 Comment
Mathias
+1 as an index doesn't have to be an integer: en.wikipedia.org/wiki/Index#Computer_science
You can get the index value with this
foreach ($arr as $key => $val)
{
$key = (int) $key;
//With the variable $key you can get access to the current array index
//You can use $val[$key] to
}
Comments
$key is the index for the current array element, and $val is the value of that array element.
The first element has an index of 0. Therefore, to access it, use $arr[0]
To get the first element of the array, use this
$firstFound = false;
foreach($arr as $key=>$val)
{
if (!$firstFound)
$first = $val;
else
$firstFound = true;
// do whatever you want here
}
// now ($first) has the value of the first element in the array
Comments
You could get the first element in the array_keys() function as well. Or array_search() the keys for the "index" of a key. If you are inside a foreach loop, the simple incrementing counter (suggested by kip or cletus) is probably your most efficient method though.
<?php
$array = array('test', '1', '2');
$keys = array_keys($array);
var_dump($keys[0]); // int(0)
$array = array('test'=>'something', 'test2'=>'something else');
$keys = array_keys($array);
var_dump(array_search("test2", $keys)); // int(1)
var_dump(array_search("test3", $keys)); // bool(false)
Comments
well since this is the first google hit for this problem:
function mb_tell(&$msg) {
if(count($msg) == 0) {
return 0;
}
//prev($msg);
$kv = each($msg);
if(!prev($msg)) {
end($msg);
print_r($kv);
return ($kv[0]+1);
}
print_r($kv);
return ($kv[0]);
}
Comments
based on @fabien-snauwaert's answer but simplified if you do not need the original key
$array = array( 'cat' => 'meow', 'dog' => 'woof', 'cow' => 'moo', 'computer' => 'beep' );
foreach( array_values( $array ) as $index=>$value ) {
// display the current index + value
echo $index . ':' . $value;
// first index
if ( $index == 0 ) {
echo ' -- This is the first element in the associative array';
}
// last index
if ( $index == count( $array ) - 1 ) {
echo ' -- This is the last element in the associative array';
}
echo '<br>';
}
$keyIS the current index.