My associative array:
$arr = array[
1 => "Value1",
2 => "Value2",
10 => "Value10"
];
Using the following code, $v is filled with $arr's values
foreach[$arr as $v]{
echo[$v]; // Value1, Value2, Value10
}
How do I get $arr's keys instead?
foreach[.....]{
echo[$k]; // 1, 2, 10
}
Foreever
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asked Dec 23, 2009 at 9:41
Robin RodricksRobin Rodricks
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2
You can do:
foreach [$arr as $key => $value] {
echo $key;
}
As described in PHP docs.
answered Dec 23, 2009 at 9:44
codaddictcodaddict
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1
If you use array_keys[], PHP will give you an array filled with just the keys:
$keys = array_keys[$arr];
foreach[$keys as $key] {
echo[$key];
}
Alternatively, you can do this:
foreach[$arr as $key => $value] {
echo[$key];
}
answered Dec 23, 2009 at 9:43
Trevor JohnsTrevor Johns
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Nobody answered with regular for loop? Sometimes I find it more readable and prefer for over foreach
So
here it is:
$array = array['key1' => 'value1', 'key2' => 'value2'];
$keys = array_keys[$array];
for[$i=0; $i < count[$keys]; ++$i] {
echo $keys[$i] . ' ' . $array[$keys[$i]] . "\n";
}
/*
prints:
key1 value1
key2 value2
*/
answered Oct 19, 2016 at 19:04
5
foreach[$array as $k => $v]
Where $k is the key and $v is the value
Or if you just need the keys use array_keys[]
answered Dec 23, 2009 at 9:44
HtbaaHtbaa
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I use the following loop to get the key and value from an associative array
foreach [$array as $key => $value]
{
echo "$key = $value
";
}
answered Aug 26, 2015 at 15:28
dmeehandmeehan
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1
The following will allow you to get at both the key and value at the same time.
foreach [$arr as $key => $value]
{
echo[$key];
}
answered Dec 23, 2009 at 9:44
Jeff BeckJeff Beck
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While arguably being less clear this method is faster by roughly a factor of roughly 3.5 [At least on the box I used to test]
$foo = array[
1 => "Value1",
2 => "Value2",
10 => "Value10"
];
while[$bar = each[$foo]]{
echo $bar[0] . " => " . $bar[1];
}
I would imagine that this is due to the fact the foreach copies the entire array before iterating over it.
answered Jul 8, 2014 at 14:49
nettuxnettux
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Use $key => $val to get the keys:
answered Dec 23, 2009 at 9:46
raphinkraphink
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0
answered Jun 7, 2017 at 14:47
Oh I found it in the PHP manual.
foreach [$array as $key => $value]{
statement
}
The current element's key will be assigned to the variable $key on each loop.
answered Dec 23, 2009 at 9:45
Robin RodricksRobin Rodricks
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foreach[$arr as $key=>$value]{
echo[$key]; // key
}
answered Dec 23, 2009 at 9:44
GravitonGraviton
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If you use nested foreach[] function, outer array's keys print again and again till inner array values end.
answered Apr 27, 2019 at 8:06