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PHP PHP Functions PHP Internal Functions PHP Array Functions

Bruno Dias
Bruno Dias
10,554 Points

Why there are two variables at array_keys loop?

Why we have two variables on the loop used on the video?

foreach(array_keys($names) as $name){
  echo "Hello, $name<br/>";

We have $names and $name. Does that mean we storing the second value inside the $name variable?

2 Answers

Kevin Korte
Kevin Korte
28,148 Points

So it's doing something like this.

$names would likely be a key value array, something like


Now, where calling a function inside a function, so first the array_key will return to use just the keys. So key => value becomes just ("student", "student", "teacher").

Now we passing our foreach a $names array that is just ``array("student", "student", "teacher"), and with every foreach, we need a working variable. It's very common to see that a variable containing an array is plural, like $names, and the working variable is the singular of that, or $name. For each item in the array we loop, so the first student key gets pulled out into the $name variable, and inside the loop we do something with $name. In this case we echo, so it would say "Hello, student", than it loops and grabs the second key, student again, and would echo a second time, "Hello, student", and it would than loop a third time, this time it would echo "Hello teacher".

The $name variable in the foreach loop is only available to the foreach loop, so when the foreach loop ends, so does access to the $name variable. But you would retain access to the $names variable that held the array.

Mike Costa
Mike Costa
Courses Plus Student 26,362 Points

Just pointing this out, but you can't have 2 keys with the same name. If you had this array:

$names = [

....the first "student" key would be overwritten. If you var dump this array you'll see:

array(2) {
  string(3) "Pam"
  string(6) "Robert"
Michael Caley
Michael Caley
5,376 Points

$names is an array, it contains all of the data.

Using the foreach command we pass the value stored in each key of the array through to $name one at a time.

If we then use array_keys we instead pass the key rather than the value to the variable $name.