front_basic/16.js_callback_hell.html at main · luail/front_basic · GitHub

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<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>콜백지옥</title>
    <script src="https://code.jquery.com/jquery-3.7.0.js"></script>
</head>
<body>
    <button onclick="callBackHell()">콜백지옥버튼</button>
    <script>
        function callBackHell(){
            $(document).ready(function(){
                $.ajax({
                    url: 'https://jsonplaceholder.typicode.com/posts/1',
                    type: 'GET',
                    dataType: 'json',
                    success: function(a){
                        // ajax와 같은 서버데이터호출 함수는 response를 parsing 진행.
                        console.log("a : ", a);
                        $.ajax({
                            url: 'https://jsonplaceholder.typicode.com/posts/1',
                            type: 'GET',
                            dataType: 'json',
                            success: function(b){
                                console.log("b : ", b);
                                $.ajax({
                                    url: 'https://jsonplaceholder.typicode.com/posts/1',
                                    type: 'GET',
                                    dataType: 'json',
                                    success: function(c){
                                        console.log("c : ", c);

                                    },
                                    error: function(e){
                                        console.log(e);
                                    }
                                })
                            },
                            error: function(e){
                                console.log(e);
                            }
                        })
                    },
                    error: function(e){
                        console.log(e);
                    }
                })
            });


            console.log("hello world");
        }
    </script>
</body>
</html>