如何将getFullMonth和getFullDate包含到自动填充的年龄？

Question

我想自动填补我的年龄后，选择出生日期，我使用的getFullYear.在选择出生日期时是否可以包括getMonth和getDate？这是我的密码。Javascript

<script type = "text/javascript">
        $(document).ready(function () {
            var age = "";
            $('#dateofbirth').datepicker({
                onSelect: function (value, ui) {
                    var today = new Date();
                    age = today.getFullYear() - ui.selectedYear;
                    $('#myAge').val(age);
                },
                changeMonth: true,
                changeYear: true
            })
        })
    </script>

Answer 1

​

$(document).ready(function() {
    $('#dateofbirth').datepicker({
      onSelect: function (value, ui) {
        var selectedDate = new Date(ui.selectedYear, ui.selectedMonth, ui.selectedDay), //Convert value to date
            dateToday = new Date(), //Get the date today.
            age = Math.floor((dateToday - selectedDate) / 31536000000) //Get the difference of dates then convert to number of years.

        $('#age').val(age);
      },
      changeMonth: true,
      changeYear: true
    });
  });

<link rel='stylesheet' href='https://cdnjs.cloudflare.com/ajax/libs/jqueryui/1.12.1/jquery-ui.min.css'>
<script src='https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js'></script>
<script src='https://cdnjs.cloudflare.com/ajax/libs/jqueryui/1.12.1/jquery-ui.min.js'></script>
<input id='dateofbirth'>
<input id='age'>

​

更新：

我没有使用(1000*60*60*24*365) = 31536000000，而是使用了(1000*60*60*24*365.25) = 31557600000。

每四年有一个额外的1天，所以我们没有循环通过它，我们只是在每年增加一个0.25来覆盖这个问题。

​

$(document).ready(function() {
    $('#dateofbirth').datepicker({
      onSelect: function (value, ui) {
        var selectedDate = new Date(ui.selectedYear, ui.selectedMonth, ui.selectedDay), //Convert value to date
            dateToday = new Date(), //Get the date today.
            age = Math.floor((dateToday - selectedDate) / 31557600000) //Get the difference of dates then convert to number of years.

        $('#age').val(age);
      },
      changeMonth: true,
      changeYear: true
    });
  });

<link rel='stylesheet' href='https://cdnjs.cloudflare.com/ajax/libs/jqueryui/1.12.1/jquery-ui.min.css'>
<script src='https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js'></script>
<script src='https://cdnjs.cloudflare.com/ajax/libs/jqueryui/1.12.1/jquery-ui.min.js'></script>
<input id='dateofbirth'>
<input id='age'>

​