php code works but for Warning: Undefined array key php

Question

The code below works in that it produces the table I want with the correct information. Unfortunately I also get 5 warning ion the page saying: Warning: Undefined array key 1 and then repeated until. key 5. I can't see any problem with the code and I have typed it pout a few times with the same results. Sorry I'm a beginner and I am totally stuck.

<?php
//create a short variable name
$document_root = $_SERVER ['DOCUMENT_ROOT'];
?>

<!DOCTYPE html>
<html>
 <head>
    <title>Bob's Auto Parts - Customer Orders</title>

    <style type="text/css">
    table, th, td {
      border-collapse: collapse;
      border: 1px solid black;
      padding: 6px;
    }

    th {
    background: #ccccff;
    }

</style>
</head>

<body>
    <h1>Bob's Auto Parts</h1>
    <h2>Customer Orders</h2>
<?php
//read in the entire file
//Each order becomes an element in the array
    $orders=file("$document_root/orders.txt");
//count the number of orders in the array
    $number_of_orders = count($orders);
    if ($number_of_orders == 0) {
        echo "<p><strong>No orders pending. <br />
            Please try again later</strong></p>";
    }
echo "<table>\n";
echo "<tr>
    <th>Order Date</th>
    <th>Tires</th>
    <th>Oil</th>
    <th>Spark Plugs</th>
    <th>Total</th>
    <th>Address</th>
    <tr>";

for ($i=0; $i<$number_of_orders; $i++) {
//split up each line
    $line = explode("\t", $orders[$i]);
//keep only the number of itmes ordered
    $line[1] = intval($line[1]);
    $line[2] = intval($line[2]);
    $line[3] = intval($line[3]);

//output each order
echo "<tr>
    <td>".$line[0]."</td>
    <td style=\"text-align: right;\">".$line[1]."</td>
    <td style=\"text-align: right;\">".$line[2]."</td>
    <td style=\"text-align: right;\">".$line[3]."</td>
    <td style=\"text-align: right;\">".$line[4]."</td>
    <td>".$line[5]."</td>
      </tr>";
}
echo "</table>";
    
?>
</body>
</html>

I'd suggest using a foreach loop instead of expecting every single order to have 5 lines. — aynber
– aynber, Commented Mar 18, 2021 at 19:06

bob_1982 · Accepted Answer · 2021-03-18 19:02:41Z

1

check if your $line array has 5 elements. something like this

for ($i=0; $i<$number_of_orders; $i++) {
 //split up each line
 $line = explode("\t", $orders[$i]);
 if(count($line)<5){
   continue;
  }
//keep only the number of items ordered

answered Mar 18, 2021 at 19:02

bob_1982

7416 silver badges17 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Alex · Accepted Answer · 2021-03-18 19:52:13Z

1

You are splitting your file order.txt by tabs, are you sure your file have tabs? (i recommend you to split each element with a ";")
Also the explode() parameter gives you an array thats starts from 0 not from 1
Is good practice checking each element before the use, something like:

    if(!isset($line[1])) {
      $line[1] = "empty line or use what logic you want";
    }

answered Mar 18, 2021 at 19:52

Alex

2602 silver badges9 bronze badges

Comments

Lucas Martins · Accepted Answer · 2021-03-18 21:25:24Z

Try to use foreach to iterate $orders array.

Something like that:

foreach ($orders as $order) {
    $line = explode("\t", $order);

    //keep only the number of itmes ordered
    $line[1] = intval($line[1]);
    $line[2] = intval($line[2]);
    $line[3] = intval($line[3]);

    //output each order
    echo "<tr>
        <td>".$line[0]."</td>
        <td style=\"text-align: right;\">".$line[1]."</td>
        <td style=\"text-align: right;\">".$line[2]."</td>
        <td style=\"text-align: right;\">".$line[3]."</td>
        <td style=\"text-align: right;\">".$line[4]."</td>
        <td>".$line[5]."</td>
        </tr>";
}

But, in this code, you are assuming that each line in the "orders.txt" file always has at least 6 informations separated by a tab (\t). Otherwise, you will receive the "Warning: Undefined array key [number]".

Depending on the case, something like this can help you:

foreach ($orders as $order) {
    if ($columns = explode("\t", $order)) {
        $row = "<tr>";

        foreach ($columns as $column) {
            $style = is_numeric($column) ? "style=\"text-align: right;\"" : "";
            $row .= "<td $style>$column</td>";
        }

        $row .= "</tr>";

        echo $row;
    }
}

Collectives™ on Stack Overflow

php code works but for Warning: Undefined array key php

3 Answers 3

Comments

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related