Question

I am attempting to write to a file using PHP. I am writing data from arrays.

Here’s my code:

    $subject = $_SESSION['subject'];
    $section = $_SESSION['section'];
    $exam1 = $_SESSION['exam1'];
    $exam2 = $_SESSION['exam2'];
    $finalexam = $_SESSION['finalexam'];
    $average = $_SESSION['average'];

    $studentArray = $_SESSION['stringArray'];

    $file = $subject . "-" . $section . ".txt";
    $fh = fopen($file, 'a');
    $size = sizeof($studentArray);
    for($i = 0; $i<$size; $i++){
        fwrite($fh, $studentArray[$i] . " " . $exam1[$i] . " " . $exam2[$i] . " " .       $finalexam[$i] . " " . $average[$i] . " ");
}

I always get this notice when I try to access this page:

 Notice: Undefined offset: 5 in C:\xampp\htdocs\CS120\MP\Grades.php on line 26

Line 26 is the one with the fwrite in the for-loop.
There’s always a notice but the code writes to the file correctly.
Is there anything that can be done to remove/solve the notice/error?

Answer 1

You can use

Method 1

array_key_exists('1',$studentArray); // check whether array position 1 exist in array $studentArray

Method 2

if (isset($studentArray1])){
  // check whether array position 1 exist in array $studentArray
}