如何獲取兩個日期和時間之間的差異並顯示在 Javascript 中運行的時間

Question

我有兩個變量我第一個變量我從日期時間選擇器中獲取日期和時間值，在第二個變量中我選擇當前日期和時間的值。 現在我想要它們之間的區別並在文本中顯示，例如計時器耗盡。

<input type="date" id="dates">
    <input type="time"  id="times">
var time=new Date().toLocaleTimeString('en-GB');
        var res = time.slice(0,-3);
        var today = new Date();
        var dd = String(today.getDate()).padStart(2, '0');
        var mm = String(today.getMonth() + 1).padStart(2, '0');
        var yyyy = today.getFullYear();
        today = yyyy + '-' + mm + '-' + dd;
        var current=today+" "+res; // Here i am getting the value of current date and time

 var datetime=dates.value+" " +times.value; // This value is from date time picker 

 var t=datetime-current;
        alert(t); //here the output is always NaN

我想要兩個日期時間之間的差異並顯示像 timmer run down 的文本

Answer 1

根據假定值更正您的代碼。

var dates = {
        value: '2019-09-06'
    };
    var times = {
        value: '10:55:00'
    };

    var time=new Date().toLocaleTimeString('en-GB');
    var res = time.slice(0,-3);
    var today = new Date();
    var dd = String(today.getDate()).padStart(2, '0');
    var mm = String(today.getMonth() + 1).padStart(2, '0');
    var yyyy = today.getFullYear();
    today = yyyy + '-' + mm + '-' + dd;
    var current=today+" "+res; // Here i am getting the value of current date and time

    var datetime=dates.value+" " +times.value; // This value is from date time picker

    var t= ( new Date( datetime ) ).getTime() - ( new Date( current ) ).getTime();
    alert(t);