index.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script src="https://cdn.bootcss.com/jquery/3.4.1/jquery.js"></script>
    <script>
        $(function () {
            const url = 'http://jsonplaceholder.typicode.com/users';
            const settings = {
                url,
                type: 'post',
                // 测试数据
                data: JSON.stringify({
                    user: {
                        username: 'scott',
                        password: 'tiger',
                    }
                }),
                success: function (response) {
                    console.log(response);
                }
            }
            $('button#payload').on('click', () => {
                $.ajax(Object.assign(settings, {contentType: 'application/json'}))
            })
            $('button#form-data').on('click', () => {ad
                $.ajax(Object.assign(settings, {contentType: 'application/x-www-form-urlencoded'}))
            })
        })
    </script>
</head>
<body>
<button id="payload">以payload的方式发送请求</button>
<button id="form-data">以form-data的方式发送请求</button>
</body>
</html>