␡
- Recipe: Setting Up an Example Server in Node.js
- Recipe: Performing a GET Request
- Recipe: Loading HTML Directly
- Recipe: Handling the Result by Using Promises
- Recipe: Handling Server Errors
- Recipe: Catching Page-not-Found Results
- Recipe: Handling Page Redirects
- Recipe: Setting Request Timeouts
- Recipe: Passing HTTP Headers
- Example: Validating Form Input on the Server Side
- Recipe: Loading XML
- Recipe: Listening to AJAX Events
- Recipe: Reading JSONP from an External Server
- Summary
This chapter is from the book
This chapter is from the book
This chapter is from the book
This chapter is from the book
Recipe: Catching Page-not-Found Results
Similarly, Listing 5.6 tests what happens when the page is not found.
Listing 5.6. Recognizing a Page-not-Found Code
00 <!DOCTYPE html>
01
02 <html lang="en">
03 <head>
04 <title>Test case: page not found</title>
05 </head>
06 <body>
07
08 <h2>Press the button to perform the request.</h2>
09
10 <button id="trigger">GET</button>
11 <br>
12 <div id="target">
13
14
15 <script src="https://code.jquery.com/jquery-1.7.2.min.js"></script>
16
17 <script>
18 // please externalize this code to an external .js file
19 $(document).ready(function() {
20
21 $('#trigger').click(function() {
22
23 $.ajax('not-found')
24 .done(function(data, xhr) {
25 $('#target').append('Unexpected success... ' +
26 '(actually not a good thing)');
27 })
28 .fail(function(xhr, text, error) {
29 $('#target').append('Failed as expected (good!). Code ' +
30 xhr.status + ' and text ' + error);
31 });
32
33 });
34
35 });
36 </script>
37 </body>
38 </html>
As expected, again, the fail() callback is called, only this time with different parameters. Although you could check the xhr.status for a specific error code, jQuery provides a setting in ajax() that looks specifically at HTTP codes. The following snippet of code could be used in the previous example, replacing line 23.
$.ajax('fail-on-purpose', {
statusCode: {
404: function() {//insert 404 handling function here},
500: function() {//insert 500 handling function here}
}
})
When you remove the comments and insert your own code, the code will be run when either a 404 or 500 HTTP status code is returned. If you leave the fail() method in place, it will also execute, giving you another error handling point.