Home  >  Article  >  Web Front-end  >  How does jsonp obtain data across domains? (code example)

How does jsonp obtain data across domains? (code example)

青灯夜游
青灯夜游forward
2019-01-05 10:24:143296browse

How does jsonp obtain data across domains? This article will introduce to you the method of jsonp to obtain cross-domain data. It has certain reference value. Friends in need can refer to it. I hope it will be helpful to you.

Jsonp cross-domain data acquisition explanation

Since the browser has a same origin policy, if you want to obtain non-original origin (protocol, domain name , if the three ports are different, they are considered non-original) The data of the page must be cross-domain

(1) jsonp principle

Since the src attribute of the script tag can access non-original js scripts, accessing the server through the src attribute will return the js code of the function, and the data we want is returned as a function parameter, and we will first define this function and return The js code can be executed

(2) jsonp implementation code

Request page

76c82f278ac045591c9159d381de2c57
100db36a723c770d327fc0aef2ce13b1
93f0f5c25f18dab9d176bd4f6de5d30e
    b2386ffb911b14667cb8f0f91ea547a76e916e0f7d1e588d4f442bf645aedb2f
9c3bca370b5104690d9ef395f2c5f8d1
6c04bd5ca3fcae76e30b72ad730ca86d
8019067d09615e43c7904885b5246f0a
    function jsonp(data){
        console.log(username)
    }
2cacc6d41bbb37262a98f745aa00fbf0
32c428c1a65afb4c21320ec475b9ffe4
2cacc6d41bbb37262a98f745aa00fbf0
8019067d09615e43c7904885b5246f0a
    $(document).ready(function(){
        var url = "http://www.example.com/jsonp.php?callback=jsonp";
        var script = $('3f1c4e4b6b16bbbd69b2ee476dc4f83a053a9cc4c2e9b9f6f911642332d34e85');
        script.attr("src",url);
        $("body").append(script);
    });
2cacc6d41bbb37262a98f745aa00fbf0
36cc49f0c466276486e50c850b7e4956
73a6ac4ed44ffec12cee46588e518a5e
7bf6f68ac33b2a6d14a606479bed8015

After that, php will return

jsonp({
    name:'niuni
})

Then the code h returned by PHP will be executed by the jsonp method of the requested page

(3) jQuery’s simple jsonp cross-domain

<script>
    function showData (data) {
        console.info(data);
    }
    $(document).ready(function () {
        $("#btn").click(function () {
            $.ajax({
                url: "http://www.example.comjsonp",
                type: "GET",
                dataType: "jsonp",// 返回数据类型
                jsonpCallback: "showData",//回调函数
                // 获取数据成功就执行success函数
                success: function (data) {
                    console.info("data");
                }
            });
        });
    });
</script>

Summary: The above is the entire content of this article, I hope it will be helpful to everyone's study. For more exciting content, you can pay attention to the relevant tutorial columns of the PHP Chinese website! ! !

The above is the detailed content of How does jsonp obtain data across domains? (code example). For more information, please follow other related articles on the PHP Chinese website!

Statement:
This article is reproduced at:cnblogs.com. If there is any infringement, please contact admin@php.cn delete