How to find the foreach index?
PhpLoopsForeachPhp Problem Overview
Is it possible to find the foreach
index?
in a for
loop as follows:
for ($i = 0; $i < 10; ++$i) {
echo $i . ' ';
}
$i
will give you the index.
Do I have to use the for
loop or is there some way to get the index in the foreach
loop?
Php Solutions
Solution 1 - Php
foreach($array as $key=>$value) {
// do stuff
}
$key
is the index of each $array
element
Solution 2 - Php
You can put a hack in your foreach
, such as a field incremented on each run-through, which is exactly what the for
loop gives you in a numerically-indexed array. Such a field would be a pseudo-index that needs manual management (increments, etc).
A foreach
will give you your index in the form of your $key
value, so such a hack shouldn't be necessary.
e.g., in a foreach
$index = 0;
foreach($data as $key=>$val) {
// Use $key as an index, or...
// ... manage the index this way..
echo "Index is $index\n";
$index++;
}
Solution 3 - Php
It should be noted that you can call key()
on any array to find the current key its on. As you can guess current()
will return the current value and next()
will move the array's pointer to the next element.
Solution 4 - Php
Owen has a good answer. If you want just the key, and you are working with an array this might also be useful.
foreach(array_keys($array) as $key) {
// do stuff
}
Solution 5 - Php
You can create $i
outside the loop and do $i++
at the bottom of the loop.
Solution 6 - Php
These two loops are equivalent (bar the safety railings of course):
for ($i=0; $i<count($things); $i++) { ... }
foreach ($things as $i=>$thing) { ... }
eg
for ($i=0; $i<count($things); $i++) {
echo "Thing ".$i." is ".$things[$i];
}
foreach ($things as $i=>$thing) {
echo "Thing ".$i." is ".$thing;
}
Solution 7 - Php
I think best option is like same:
foreach ($lists as $key=>$value) {
echo $key+1;
}
it is easy and normally
Solution 8 - Php
PHP arrays have internal pointers, so try this:
foreach($array as $key => $value){
$index = current($array);
}
Works okay for me (only very preliminarily tested though).
Solution 9 - Php
Jonathan is correct. PHP arrays act as a map table mapping keys to values. in some cases you can get an index if your array is defined, such as
$var = array(2,5);
for ($i = 0; $i < count($var); $i++) {
echo $var[$i]."\n";
}
your output will be
2
5
in which case each element in the array has a knowable index, but if you then do something like the following
$var = array_push($var,10);
for ($i = 0; $i < count($var); $i++) {
echo $var[$i]."\n";
}
you get no output. This happens because arrays in PHP are not linear structures like they are in most languages. They are more like hash tables that may or may not have keys for all stored values. Hence foreach doesn't use indexes to crawl over them because they only have an index if the array is defined. If you need to have an index, make sure your arrays are fully defined before crawling over them, and use a for loop.
Solution 10 - Php
I use ++$key
instead of $key++
to start from 1. Normally it starts from 0.
@foreach ($quiz->questions as $key => $question)
<h2> Question: {{++$key}}</h2>
<p>{{$question->question}}</p>
@endforeach
Output:
Question: 1
......
Question:2
.....
.
.
.
Solution 11 - Php
I solved this way, when I had to use the foreach index and value in the same context:
$array = array('a', 'b', 'c');
foreach ($array as $letter=>$index) {
echo $letter; //Here $letter content is the actual index
echo $array[$letter]; // echoes the array value
}//foreach
Solution 12 - Php
I normally do this when working with associative arrays:
foreach ($assoc_array as $key => $value) {
//do something
}
This will work fine with non-associative arrays too. $key will be the index value. If you prefer, you can do this too:
foreach ($array as $indx => $value) {
//do something
}
Solution 13 - Php
foreach(array_keys($array) as $key) {
// do stuff
}
Solution 14 - Php
I would like to add this, I used this in laravel to just index my table:
- With $loop->index
- I also preincrement it with ++$loop to start at 1
My Code:
@foreach($resultsPerCountry->first()->studies as $result)
<tr>
<td>{{ ++$loop->index}}</td>
</tr>
@endforeach