根据“日期” HTML元素计算年龄

Adi Solar 发表于 Dev

阿迪太阳能

我有一个带有“日期”元素和提交按钮的HTML表单。有2个功能。一种是在“ date” HTML元素中根据给定的出生日期计算年龄。另一个功能是将年龄与最小允许年龄进行比较。我需要帮助来完成它。在代码注释中查看我的问题。是的，我看到了其他类似的问题。我想学习，而不仅仅是复制/粘贴。如果我了解自己的代码/语法有什么问题，那么我会学得更好。提前致谢。

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0  Transitional//EN""http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml">
<head>
   <title></title>
</head>
<body>
 <script type="text/javascript">

    var minAge = 18;

    var curDate = new Date();

    var curr_year = curDate.getFullYear();
    var curr_month = curDate.getMonth();


    //Calculates age from given Birth Date in the form//
    function _calcAge() {

        var dt1 = document.getElementById('date').value;
        var birth_date = new Date(dt1);

        var birth_year = birth_date.getFullYear();
        var birth_month = birth_date.getMonth();
        var calc_year = curr_year - birth_year;
        var calc_month = curr_month - birth_month;

        //The following below is what I am not sure about. 
        //I need to combine years and months and
        //convert them into a string??? Is this syntax dead wrong?

    var final_result = (calc_year && "." && calc_month).toString();

        // final result should be a number with a decimal point, example: 35.5
        final_result = parseFloat;

        return (final_result);
        alert(final_result);
    }

    //Compares calculated age with minimum age and acts according to rules//
    function _setAge() {

        var age = _calcAge();
        //alert("my age is " + age);
        if (age < minAge) {
            alert("You are not allowed into the site. The minimum age is 18!");
        } else

            alert("Welcome to my Site");
            window.open(main.htm, _self);

    }


    </script>

     <form>
      Date Of Birth: <input type="date" name="date of birth" id="date" />
      <input type="submit" name="submit" id="submit" onClick="_setAge();" />

     </form>

    </body>
   </html>

阿迪太阳能

我设法使它起作用。信用也去https://stackoverflow.com/users/444991/matt因为我向他借这里的一部分：https://stackoverflow.com/a/4076440/3189118

 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

    <html xmlns="http://www.w3.org/1999/xhtml">
    <head>
     <title></title>
   </head>
     <body>
      <script type="text/javascript">

      var minAge = 18;
      var today = new Date()
      //Calculates age from given Birth Date in the form//
       function _calcAge(birthDate, givenDate) {
        givenDate = new Date(today);
        var dt1 = document.getElementById('date').value;
        var birthDate = new Date(dt1);
        var years = (givenDate.getFullYear() - birthDate.getFullYear());

        if (givenDate.getMonth() < birthDate.getMonth() ||
     givenDate.getMonth() == birthDate.getMonth() && givenDate.getDate() < birthDate.getDate()) {
            years--;
        }

        return years;
    }

    //Compares calculated age with minimum age and acts according to rules//
    function _setAge() {

        var age = _calcAge();
        if (age < minAge) {
            alert("You are not allowed into the site. The minimum age is 18!");
        } else

            alert("Welcome to my Site");


    }


</script>

<form>
    Date Of Birth: <input type="date" name="date of birth" id="date" />
    <input type="submit" name="submit" id="submit" onClick="_setAge();" />

</form>