When a user selects startDate and endDate, I want start date to be displayed in other text box

I want to select the startDate from this field:

@Html.EditorFor(model => model.TimePeriod.StartDate, new { htmlAttributes = new { @class = "form-control datepicker", @id="StartDate",@onchange="addDates()" } })
@Html.ValidationMessageFor(model => model.TimePeriod.StartDate, "", new { @class = "text-danger" })

Here I want to autopopulate that start date here

<td>
                    @Html.EditorFor(model => model.DailyRegister.Date, new { htmlAttributes = new { @class = "form-control", required = "required", @id = "date1" } })
                    @Html.ValidationMessageFor(model => model.DailyRegister.Date, "", new { @class = "text-danger" })
                    <script>
                            function addDates() {
                            document.getElementById("date1").value = document.getElementById("StartDate");
                        }
                    </script>
                </td>

Running above code gives this result

>Solution :

It might be a silly question, but have you tried getting the value of the start date field instead?

document.getElementById("date1").value = document.getElementById("StartDate").value;

Depending on when you call the addDates() function you might need an event listener as well.