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PHP PHP Arrays and Control Structures PHP Loops For Looping

Teacher Russell
Teacher Russell
16,873 Points
Posted by Teacher Russell
Teacher Russell
16,873 Points

php , for looping 2 objectives

Did I miss a lesson where we practiced isset funtions? The second challenge is telling me to use one.

index.php 
<?php
$facts = array(
    57 => ' on Heinz ketchup bottles represents the number of varieties of pickles the company once had.',
    2 => ' is the approximate hours a day Giraffes sleeps',
    18 => ' is the average hours a Python sleeps per day',
    10 => ' per cent of the world is left-handed.',
    11 => ' Empire State Buildings, stacked one on top of the other, would be required to measure the Gulf of Mexico at its deepest point.',
    98 => '% of the atoms in your body are replaced every year',
    69 => ' is the largest number of recorded children born to one woman',
);
//add your loop below this line

for ($num = 1; $num <= 100; $num++) {
  echo $num . "<br />\n";
}

1 Answer

Adam Ridgley
Adam Ridgley
12,255 Points

If the video didn't mention the isset function then here's the code you need.

  if (isset($facts[$num])) {
   echo $facts[$num];
  }

The isset function is pretty simple, it checks if the variable you pass it to see if it is set. The above code checks that the array element exists with that key and shows the array element value if it does.

Teacher Russell
Teacher Russell
16,873 Points
Teacher Russell
Teacher Russell
16,873 Points

Thanks, very much! Seems like a strange thing to do, introducing a new function in the middle of a challenge practicing " for loops ". So, I had seen isset on youtube, in videos using php to build forms. I thought maybe it was just to check if there was anything stored in a variable yet. It checks to see if there's a match between some variable and a value in an array?

Adam Ridgley
Adam Ridgley
12,255 Points

In this case it’s checking that the array entry exists with the specified key, the more you use the function the more it will make sense.