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17,062 Pointsquestion about the use of isset() in the challange
So i figure out the challange but im not 100% sure what's going on:
<?php
for ( $i = 1; $i <= 100; $i++ ) {
echo $i . "\n";
//if the key exists in the array
if(isset($facts[$i])) {
//we show the value of this key
echo $facts[$i] . "\n";
}
}
?>
in the if statment isset is checking if there is an element in the current position of the $i , the $i is lets say in the 57 iteration so
$facts[$i] === $facts["57"]
if there is an element that exists in the current iteration the evulation of the if statement return TRUE if not it return NULL. so in the above example $facts["57"] return true because $i has the same value as one of the existing keys of the $facts array
am i right on how the use of isset() function works here, that's what is happening under the hood?
1 Answer
![KRIS NIKOLAISEN](https://secure.gravatar.com/avatar/65d74a723997b41a80d2d909c6e06960?s=96&d=https%3A%2F%2Fecs-static.teamtreehouse.com%2Fassets%2Fcontent%2Fdefault_avatar-445fbbabfc8dc9188fb5967fe43322ee0c3e0dd1e10f378bf8343784af5a13eb.webp&r=pg)
KRIS NIKOLAISEN
54,969 PointsAccording to the PHP docs isset returns TRUE if var exists and has any value other than NULL. FALSE otherwise.