谢谢你，彼得，现在我改代码了。

<input type='date' id='d1' name='d1'>

<script type="text/javascript">
var d1 = new Date();
var y1= d1.getFullYear();
var m1 = d1.getMonth()+1;
if(m1<10)
    m1="0"+m1;
var dt1 = d1.getDate();
if(dt1<10)
dt1 = "0"+dt1;
var d2 = y1+"-"+m1+"-"+dt1;
document.getElementById('d1').value=d2;
</script>

这是非常简单的应用下面的代码，使用PHP

<input type="date" value="<?= date('Y-m-d', time()); ?>" />

Date函数将通过Date in time()返回当前日期。

如果你正在使用ruby，你可以使用这个来设置默认值为今天的日期和时间:

<input type="datetime-local" name="time" value="<%= Time.now.strftime('%Y-%m-%dT%H:%M') %>" />

HTML

<input type="date" id="theDate">

JQuery

$(document).ready(function() {
    var date = new Date();

    var day = date.getDate();
    var month = date.getMonth() + 1;
    var year = date.getFullYear();

    if (month < 10) month = "0" + month;
    if (day < 10) day = "0" + day;

    var today = year + "-" + month + "-" + day +"T00:00";       
    $("#theDate").attr("value", today);
});

demo

如果你不想使用jQuery，你可以这样做

JS

var date = new Date();

var day = date.getDate();
var month = date.getMonth() + 1;
var year = date.getFullYear();

if (month < 10) month = "0" + month;
if (day < 10) day = "0" + day;

var today = year + "-" + month + "-" + day;       
document.getElementById("theDate").value = today;

demo

TS

const date = new Date()
const year = date.getFullYear()

let month: number | string = date.getMonth() + 1
let day: number | string = date.getDate()

if (month < 10) month = '0' + month
if (day < 10) day = '0' + day

const today = `${year}-${month}-${day}`    
document.getElementById("theDate").value = today;

对于那些使用ASP VBScript的人

<%
'Generates date in yyyy-mm-dd format
Function GetFormattedDate(setDate)
strDate = CDate(setDate)
strDay = DatePart("d", strDate)
strMonth = DatePart("m", strDate)
strYear = DatePart("yyyy", strDate)
If strDay < 10 Then
  strDay = "0" & strDay
End If
If strMonth < 10 Then
  strMonth = "0" & strMonth
End If
GetFormattedDate = strYear & "-" & strMonth & "-" & strDay
End Function
%>

然后在body中，元素应该是这样的

<input name="today" type="date" value="<%= GetFormattedDate(now) %>" />

干杯!

new Date().getFullYear()+"-"+ ((parseInt(new Date().getMonth())+1+100)+"").substring(1)