Difference between “as $key => $value” and “as $value” in PHP foreach

Question

I have a database call and I\'m trying to figure out what the $key => $value does in a foreach loop.

The reason I ask is because both these

Answer 1

The difference is that on the

foreach($featured as $key => $value){
 echo $value['name'];
}

you are able to manipulate the value of each iteration's $key from their key-value pair. Like @djiango answered, if you are not manipulating each value's $key, the result of the loop will be exactly the same as

foreach($featured as $value) {
  echo $value['name']
}

Source: You can read it from the PHP Documentation:

The first form loops over the array given by array_expression. On each iteration, the value >of the current element is assigned to $value and the internal array pointer is advanced by >one (so on the next iteration, you'll be looking at the next element).*

The second form will additionally assign the current element's key to the $key variable on >each iteration.

---

If the data you are manipulating is, say, arrays with custom keys, you could print them to screen like so:

$array = ("name" => "Paul", "age" => 23);

foreach($featured as $key => $value){
 echo $key . "->" . $value;
}

Should print:

name->Paul

age->23

And you wouldn't be able to do that with a foreach($featured as $value) with the same ease. So consider the format above a convenient way to manipulate keys when needed.

Cheers