Error - Passing an array from PhP to jQuery using JSON
Question
I apologise, since I know this has been asked before , more than once .
I've been struggling with this little bugger for quite a few hours now, and I cannot seem to find my mistake.
The problem is simple - I have a PhP array which I want to pass over, from the server side to the client side, using jQuery AJAX with the data in JSON format.
The code for my Client-side Ajax call is
$.ajax({
url: 'php/test/pass_array.php',
method: 'POST',
data: {test1: 'abc', test2: 'cde'}, //Random input data
dataType: 'json',
success: function(response_data)
{
console.log(response_data);
},
error: function(jqXHR, textStatus, errorThrown)
{
console.log(arguments);
console.log('Error: ' + errorThrown + ' ' + textStatus + ' ' + jqXHR);
}
});
And the code for my server-side pass_array.php script is
header('Content-type: application/json; charset=utf-8');
echo json_encode(array("Name"=>"Johnny")); //Build JSON object from the array
As you can see, this is pretty basic, but it's not working. On the client side, the AJAX response is never received.
When I check the browser console log, I get
Error: SyntaxError: Unexpected token parsererror [object Object]
What the devil am I doing wrong?
All my files are in UTF-8 encoding. This also works if I remove the dataType: 'json' and the heading() on the PhP side. In that case, I get the following string:
{"Name":"Johnny"}
UPDATE
Commenting out the header() code in the PhP side makes the console show the following error:
Uncaught SyntaxError: Unexpected token o
How can there by syntax errors? I create a PhP array and encode it using json_encode.
UPDATE #2
Fixed it.
On my PhP file I had (only one more!) line
include '../core/db_io.php';
I commented that line out and it worked fine.
This file contains methods to query my databases. Since I did not call any methods or objects from this file, I left it uncommented - thinking it made no difference.
It looks like including that db_io.php file added a Byte Order Mark character (\) to the JSON string.
The complete string being sent to the Client side was
\ufeff{"Name":"Johnny"}
It seems this db_io.php file was encoded with BOM. Changing its encoding (using notepad++) fixed that.
Amazing how a simple include instruction can mess up an AJAX call.
4 answers
solution1
1 2013-12-09 01:32:41
Make sure your PHP script starts with <?php
Update 1:
I made two files on my localhost - index.html
<html>
<head>
<script src="//code.jquery.com/jquery-1.10.2.min.js"></script>
</head>
<body>
<script>
$.ajax({
url: 'pass_array.php',
method: 'POST',
data: {test1: 'abc', test2: 'cde'}, //Random input data
dataType: 'json',
success: function(response_data)
{
console.log(response_data);
},
error: function(jqXHR, textStatus, errorThrown)
{
console.log(arguments);
console.log('Error: ' + errorThrown + ' ' + textStatus + ' ' + jqXHR);
}
});
</script>
</body>
</html>
pass_array.php
<?php
header('Content-type: application/json; charset=utf-8');
echo json_encode(array("Name" => "Johnny"));
The result of the AJAX call in the console is:
Object {Name: "Johnny"}
Make sure the url is correctly accessing the right php file.
You can check any "XHR" requests (AJAX) in Chrome's inspector under the "Network" tab.
solution2
1 2013-12-09 01:38:18
Try checking out if your ajax function is being triggered and if any request is even being sent to your php code. For example maybe there is some syntax in your ajax script or you have not provided the url of your php file.
solution3
1 ACCPTED 2013-12-09 01:57:48
Fixed it.
On my PhP file I had (only one more!) line
include '../core/db_io.php';
I commented that line out and it worked fine.
This file contains methods to query my databases. Since I did not call any methods or objects from this file, I left it uncommented - thinking it made no difference.
I still don't understand tho - I'm not using that file in any way - other than include it. Why should it interfere?
Thanks for the ideas. Peace!
solution4
0 2013-12-09 01:40:28
Error: SyntaxError: Unexpected token
U have problems with 'token' variable. Mb u use CMS or Framework?
Try
console.log(arguments);
And also, u can try send
header('Content-type: application/json');
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