<input type="date" value=""> 的value值，只能是"yyyy-MM-dd"，这样的，例如：“2020-9-27” 这样

代码如下：

<script src="http://code.jquery.com/jquery-2.1.4.min.js"></script>
<input type="date" class="defaultTxt" id="txtEnteringDate_edit" />
<script>
     $.ajax({
                async: false,
                type: "get",
                url: "/Recommend/GetRecommendById",
                data: {
                    id: id
                dataType: "json",
                success: function (json) {
        $("#txtEnteringDate_edit").val(dayFormat(json.EnteringDate.replace("T00:00:00","")));         
        //日期格式化 
        function dayFormat(dt) {
            var date = new Date(dt);
            var year = date.getFullYear();
            var month = date.getMonth() + 1;
            var day = date.getDate();
            if (month < 10) {
                month = "0" + month;
            if (day < 10) {
                day = "0" + day;
            var nowDate = year + "-" + month + "-" + day;
            return nowDate;
</script>

初始化，日期控件为今天：

日期：<input type="date" id="dtDate" />
<script>
      $(function () {
            DateNow();
        function DateNow() {
             var now = new Date();
            var nowYear = now.getFullYear(); //年
            var nowMonth = now.getMonth() + 1 < 10 ? "0" + (now.getMonth() + 1) : now.getMonth(); //月
            var nowDay = now.getDate() < 10 ? "0" + now.getDate() : now.getDate(); //日期
            var nowDate = nowYear + "-" + nowMonth + "-" + nowDay;
            $("#dtDate").val(nowDate);
</script>

其他： https://blog.csdn.net/u014063717/article/details/50914466