Php ajax call for same php script response null

Question

I am developing a single page script i.e. category.php for category management. - This script have an input button to invoke AJAX call. ``` <input type="button" id="btn" /> ``` Jquery code to bind click event and call ajax. I want json response. ``` $(document).ready(function(e) { $('#btn').click(function(e) { id=1; jQuery.ajax({ type: 'post', url: 'category.php', success: function(data) { if(data.rstatus==1){ alert(data.text); }else alert(data); }, data:{'id':id} }); }); }); ``` A php code to entertain AJAX call. ``` if(!empty($_SERVER['HTTP_X_REQUESTED_WITH']) && strtolower($_SERVER['HTTP_X_REQUESTED_WITH']) == 'xmlhttprequest') { $jsonResponse=array('rstatus'=>1,'id'=>$_POST['id']); header("Content-type: application/json"); json_encode($jsonResponse); die(); } ``` Problem: This ajax call is unable to produce correct response in call back function, and cause error in firebug console. TypeError: data is null In FIREBUG Headers are as follow: `Response Headers` ``` > Cache-Control no-…

Accepted Answer

It's look like your response content is empty. You forgot an `echo`.

```
if(!empty($_SERVER['HTTP_X_REQUESTED_WITH']) && strtolower($_SERVER['HTTP_X_REQUESTED_WITH']) == 'xmlhttprequest') {
    $jsonResponse=array('rstatus'=>1,'id'=>$_POST['id']);
    header("Content-type: application/json"); 
    echo json_encode($jsonResponse); 
    die(); 
}
```

If you want to response a json, you must put it in the response content. In Php, you just have to use `echo` to put something in the response content.

Php ajax call for same php script response null

Solution

Problem