JSONP Solution Ajax Cross-Domain code example

There are two subdomains, a.xx.com and b.xx.com, now I send an AJAX request in a.xx.com a page b.xx.com a method in a controller, want to get the return data, but return state 302, should be a cross-domain problem unresolved.

One way to solve the Ajax Cross-domain problem is to use Jsonp,jquery to encapsulate Ajax methods and Getjason methods, and cross domain issues in the work, documenting JSONP usage and examples.

(function ($) {
var url = '/scripts/jquery4u-sites.json?callback=? ';

$.ajax ({
Type: ' Get ',
Url:url,
Async:false,
Jsonpcallback: ' Jsoncallback ',
ContentType: "Application/json",
DataType: ' Jsonp ',
Success:function (JSON) {
Console.dir (json.sites);
},
Error:function (e) {
Console.log (E.message);
}
});

}) (JQuery);

This is the AJAX approach to jquery, using JSONP to define parameter references as code. Often the requested URL is followed by a callback=?, the question mark can be followed by a parameter, or you can leave blank. This example does not do a specific explanation, only record usage.

/* Loading JSON objects using JSONP */
(function ($) {
var url = '/scripts/jquery4u.settings.json ';
$.ajax ({
Type: ' Get ',
Url:url,
Async:false,
ContentType: "Application/json",
DataType: ' Jsonp '
});
}) (JQuery);

This example is a direct request to the JSON file.

$.getjson (' Ajax/test.json ', function (data) {
var items = [];

$.each (data, function (key, Val) {
Items.push (' <li id= ' + key + ' "> ' + val + ' </li> ');
});

$ (' <ul/> ', {
' Class ': ' My-new-list ',
Html:items.join (")"
}). Appendto (' body ');
});

In this case, the Getjson method request using jquery, the Getjson method automatically supports JSONP, is a jquery encapsulated good.

<script>
The client uses the Getjson method to request a script on another machine
The browser generates a random callback parameter
$.getjson ("/new/ajax_jsonp.php?callback=?", function (JSON) {
alert (json.website);
});
</script>

Getjson cross-Domain Request example, note that the URL behind the band? Callback=, otherwise is the general request JSON return data, not cross-domain, with this, plus no parameters depending on the situation, that is, Jsonp Cross-domain.

As for the parameters mentioned above, take a callback=?

Starting with version 1.2, JQuery has local support for JSONP callbacks. If you specify a JSONP callback, you can load the JSON data that is located in another domain, and the callback syntax is: url?callback=? JQuery automatically will? Replace with the name of the build function to invoke.

You can also give callback with parameters, such as? Callback=hello, then PHP (or other language programs) first get $_get[' callback ', the output is: $_get[' callback ']+ (JSON format data), Then on the page, there is a function hello () method to process the returned data. (This is just a general description of the process, generally do not add callback parameters, directly with a question mark)