undetermined string literal error - php

Question

How do I fix this unterminated string literal error. What does this error mean and how can it be fixed
Below is the full code:
<?php
session_start();
if(isset($_POST['fileImage'])){
$idx = count($_POST ['fileImage']) -1 ;
$output = isset($_POST ['fileImage'][$idx]) ? $_POST ['fileImage'][$idx]['name'] : "";
}
?>
function stopImageUpload(success) {
var imageNameArray = ['<?php echo json_encode($output); ?>'];
var result = '';
if (success == 1) {
result = '<span class="msg">The file was uploaded successfully!</span><br/><br/>';
for (var i = 0; i < imageNameArray.length; i++) {
$('.listImage').append(imageNameArray[i] + '<br/>');
}
}
else {
result = '<span class="emsg">There was an error during file upload!</span><br/><br/>';
}
return true;
}​

Answer 1

It means that there's something wrong with your quotes (an extra single quote in the echo'd content, or a line feed) and it's messing up the parser. Make sure any characters that are special in JS (quotes, line breaks etc) are properly escaped.
json_encode does this for you.

Answer 2

A better solution might look like this:
<?php
session_start();
$results = array();
if(isset($_POST['fileImage'])){
// not entirely sure what you're trying to achieve here
// so just replicating the logic you already had
// but I'm sure there's a better way to do whatever this is trying to do
$idx = count($_POST['fileImage']) -1 ;
$results[] = isset($_POST['fileImage'][$idx]) ? $_POST ['fileImage'][$idx]['name'] : "";
}
?>
function stopImageUpload(success) {
var imageNameArray = <?php echo json_encode($results); ?>;
var result = '';
if (success == 1) {
result = '<span class="msg">The file was uploaded successfully!</span><br/><br/>';
for (var i = 0; i < imageNameArray.length; i++) {
$('.listImage').append(imageNameArray[i] + '<br/>');
}
} else {
result = '<span class="emsg">There was an error during file upload!</span><br/><br/>';
}
// you might want to use the "result" variable before returning
return true;
}​
What changed? I removed the [] around the output of json_encode and made the array in PHP instead of JS. This way, when you do post the form, $results will be an array with a single element, and when you don't, it'll be an empty array. The rest of the logic should work just like before, but do read the comments I added.