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PHP Build a Simple PHP Application Integrating with PayPal Creating Paypal Buttons

Posted by Jose Mora Hernandez
Jose Mora Hernandez
2,909 Points

Undefined index: 102 in C:\xampp\htdocs\shirt.php on line 5

I'm not sure what I'm doing wrong. Can anyone tell me what does that message mean? this is my code

<?php include("inc/products.php");

$product_id = $_GET["id"];
$product = $products[$product_id];

?><pre><?php

echo $product_id . "\n";
var_dump($product);

?></pre>

5 Answers

Jose Mora Hernandez
Jose Mora Hernandez
2,909 Points

what do you mean? why am I posting the codes? to seek some help from you guys if possible maybe that way the error message will disappear.

David Omar
David Omar
5,676 Points
David Omar
David Omar
5,676 Points

Ok I see your problem, 

<?php
$product_id = $_GET["id"];
$product = $products[$product_id];
?>

you are getting a error because you loaded up shirt.php but no $_GET variable was set. There is a function in php called isset to check whether its set or not

<?php
if(isset($_GET['id']))
{
 //do something
} else
{
// do something else
}
?>

$_GET variables are set through the url bar, so to set $_GET['id'], the url has to be shirt.php/?id=107

Any clearer now?

David Omar
David Omar
5,676 Points
David Omar
David Omar
5,676 Points

Undefined Index means your trying to access the array index that does not exist.

$product = $products[$product_id];

In this line your are assigning the variable $product to the value in the $products array with index of $product_id

Andreas cormack
seal-mask
.a{fill-rule:evenodd;}techdegree seal-36
Andreas cormack
Python Web Development Techdegree Graduate 33,011 Points
Andreas cormack
.a{fill-rule:evenodd;}techdegree seal-36
Andreas cormack
Python Web Development Techdegree Graduate 33,011 Points

its looking for an index that is not there. in your query string is the ID in caps can you should what your query string look like?? apart from that cannot see anything wrong with your code.

Jose Mora Hernandez
Jose Mora Hernandez
2,909 Points

everything seems to be lowercase so i think I'm good in that part.

Jose Mora Hernandez
Jose Mora Hernandez
2,909 Points
Jose Mora Hernandez
Jose Mora Hernandez
2,909 Points

Well this is my products.php coding page

<?php 

$products = array();
$products [101] = array(
    "name" => "Logo Shirt, Red",
    "img" => "img/shirts/shirt-101.jpg",
    "price" => 18, 
    "paypal"=> "XTP4CGPD626RN"
);

$products[102] = array(
    "name" => "Mike the Frog Shirt, Black",
    "img" => "img/shirts/shirt-102.jpg",
    "price" => 20,
    "payal"=> "CCDN6PD5PH7DJ"
);
$products[103] = array(
    "name" => "Mike the Frog Shirt, Blue",
    "img" => "img/shirts/shirt-103.jpg",    
    "price" => 20,
    "paypal"=> "CT9LBHSJDL7MS"
);
$products[104] = array(
    "name" => "Logo Shirt, Green",
    "img" => "img/shirts/shirt-104.jpg",    
    "price" => 18,
    "paypal"=> "4YPMZA4YC49S2"
);
$products[105] = array(
    "name" => "Mike the Frog Shirt, Yellow",
    "img" => "img/shirts/shirt-105.jpg",    
    "price" => 25,
    "paypal"=> "T25RNN786DM46"
);
$products[106] = array(
    "name" => "Logo Shirt, Gray",
    "img" => "img/shirts/shirt-106.jpg",    
    "price" => 20,
    "paypal"=> "2LCZD8F8TX7TY"
);
$products[107] = array(
    "name" => "Logo Shirt, Turquoise",
    "img" => "img/shirts/shirt-107.jpg",    
    "price" => 20,
    "paypal"=>"7UCD7CUNU8XDN"
);
$products[108] = array(
    "name" => "Logo Shirt, Orange",
    "img" => "img/shirts/shirt-108.jpg",    
    "price" => 25,
    "paypal"=>"VHX8VJXEAGGK8"
);

?>

Im also posting my shirts.php code as well I know is a lot to go through but man I'm breaking my head at the moment.

<?php include("inc/products.php"); ?><?php
$pageTitle = "Mike's Full Catalog of Shirts";
$section = "shirts";
include('inc/header.php'); ?>

<div class="section shirts page">

    <div class="wrapper">

    <h1>Mike&rsquo;s Full Catalog Of Shirts</h1>

        <ul class="products">
            <?php foreach($products as $product_id=> $product) {
                echo "<li>";
                echo '<a href="shirt.php? id= ' . $product_id . '">';
                echo '<img src="' . $product["img"] . '" alt="' . $product["name"] . '">';
                echo "<p>View Details</p>";
                echo "</a>";
                echo "</li>";
            } 
        ?>
        </ul>

        </div>

    </div>

<?php include('inc/footer.php') ?>
David Omar
David Omar
5,676 Points
David Omar
David Omar
5,676 Points

I don't get it what are you trying to do with this?

Jose Mora Hernandez
Jose Mora Hernandez
2,909 Points
Jose Mora Hernandez
Jose Mora Hernandez
2,909 Points

Yeah a little bit more clear now unfortunately though, on the video tutorials I don't think he has gone over that element yet.