Ajax和Google图书

Question

I am sending some Google Book info to my db by retrieving JSON data. My code is below

$.ajax({
     type: 'POST',
     url: 'addIsbnScript.php',
     data: {
         'isbn' : isbn,
         'title' : entry.volumeInfo.title,
         'subtitle' : entry.volumeInfo.subtitle||'not available',
         'author' : entry.volumeInfo.authors[0]||'not available',
         'category' : entry.volumeInfo.categories ||'not available',
         'description' : entry.volumeInfo.description ||'not available'
     },
});

addIsbnScript.php

$title = $_POST['title'];
$category = $_POST['category'];
$author = $_POST['author'];
$isbn = $_POST['isbn'];
$subtitle = $_POST['subtitle'];
$description = $_POST['description'];

$query = $conn->prepare("INSERT INTO `book` (title,category,author,isbn,subtitle,description) VALUES (?,?,?,?,?,?)");
$query->bind_param('ssssss',       
        $title,
        $category,
        $author,
        $isbn,
        $subtitle,
        $description
        );
$query->execute();

Most of the time all of the data sends successfully, however I have noticed two things;

• If there is more than one category in the JSON, the word 'Array' is sent to my db.

• If there is no author present in the JSON my script doesn't run and I receive the following error in the console;

  Uncaught TypeError: Cannot read property '0' of undefined

Very new to JS and PHP so any advice and direction is welcome.

Answer 1

You'll want to check entry.volumeInfo.authors exists before using the array subscript [0].

'author' : (entry.volumeInfo.authors ? entry.volumeInfo.authors[0] : 'not available'),

If categories is a similar field to authors, you can do something similar for categories:

'category' : (entry.volumeInfo.categories ? entry.volumeInfo.categories[0] : 'not available'),

Above, I'm using a ternary operator to add a conditional inline.