Javascript 如何使用MaskedEditExtender在文本框中添加天数

我想使用javascript在文本更改事件中添加显示在文本框中的日期天数。请帮帮我

<tr id="AbsentDays" runat="server">
    <td align="right" style="width: 33%">
        <asp:Label ID="Label9" runat="server" Text="No of days"></asp:Label>
    </td>
    <td id="Td5" runat="server">&nbsp;:&nbsp;
    </td>
    <td id="Td6" align="left" colspan="3" runat="server">
        <asp:TextBox runat="server" ID="txtDayAbsent" Width="80px"
            onchange="javascript: ontextchanged();"></asp:TextBox>
    </td>
</tr>


<tr>

    <td align="right">
        <asp:Label ID="lblDurationFrom" runat="server" Text="Duration From"></asp:Label>
    </td>
    <td style="width: 1%;">&nbsp;:&nbsp;
    </td>
    <td style="width: 36%">
        <asp:TextBox ID="txtDurationFrom" runat="server" Width="80px"></asp:TextBox>
        <cc1:maskededitextender id="MaskedEditExtender2" runat="server" targetcontrolid="txtDurationFrom"
            mask="99/99/9999" masktype="Date" errortooltipenabled="True" culturename="en-GB"
            cultureampmplaceholder="AM;PM" culturecurrencysymbolplaceholder="£" culturedateformat="DMY"
            culturedateplaceholder="/" culturedecimalplaceholder="." culturethousandsplaceholder=","
            culturetimeplaceholder=":" enabled="True" />
        <cc1:calendarextender id="CalendarExtender1" runat="server" targetcontrolid="txtDurationFrom"
            format="dd/MM/yyyy" enabled="True" />
    </td>

    <td align="right">
        <asp:Label ID="lblDurationTo" runat="server" Text="Duration To"></asp:Label>
    </td>
    <td style="width: 1%;">&nbsp;:&nbsp;
    </td>
    <td>
        <asp:TextBox ID="txtDurationTo" runat="server" Width="80px"></asp:TextBox>
        <cc1:maskededitextender id="MaskedEditExtender1" runat="server" targetcontrolid="txtDurationTo"
            mask="99/99/9999" masktype="Date" errortooltipenabled="True" culturename="en-GB"
            cultureampmplaceholder="AM;PM" culturecurrencysymbolplaceholder="£" culturedateformat="DMY"
            culturedateplaceholder="/" culturedecimalplaceholder="." culturethousandsplaceholder=","
            culturetimeplaceholder=":" enabled="True" />
        <cc1:calendarextender id="CalendarExtender2" runat="server" targetcontrolid="txtDurationTo"
            format="dd/MM/yyyy" enabled="True" />
    </td>

</tr>

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Javascript

function ontextchanged()
{
    var dayAbsent = document.getElementById('<%=txtDayAbsent.ClientID%>').value;
    var myDate = new Date((document.getElementById('<%=txtDurationTo.ClientID%>')).value);
    myDate.setDate(myDate.getDate() + parseInt(dayAbsent));
}    

函数ontextchanged（）
{
var day缺席=document.getElementById（“”）.value；
var myDate=新日期（（document.getElementById（“”））.value）；
myDate.setDate（myDate.getDate（）+parseInt（day缺席））；
}    

在txtday缺席的更改事件中我想在txtdaurationto中添加天数

---

现在，如何使用dd/mm/yyyy格式将此日期设置为txtDurationTo文本框

您需要附加日期的日、月和年部分，然后使用require格式创建日期。像这样

 <script type="text/javascript">
        function ontextchanged() {
            var dayAbsent = document.getElementById('<%=txtDayAbsent.ClientID%>').value;
            var myDate = new Date((document.getElementById('<%=txtDurationTo.ClientID%>')).value);
            myDate.setDate(myDate.getDate() + parseInt(dayAbsent));

            var dd = myDate.getDate();
             var mm = myDate.getMonth() + 1; //January is 0!
            var yyyy = myDate.getFullYear();
            if (dd < 10) { dd = '0' + dd } if (mm < 10) { mm = '0' + mm }
            var today = dd + '/' + mm + '/' + yyyy;              

             document.getElementById('<%=txtDurationTo.ClientID%>').value = today;
             alert(today);
        }    </script>

函数ontextchanged（）{
var day缺席=document.getElementById（“”）.value；
var myDate=新日期（（document.getElementById（“”））.value）；
myDate.setDate（myDate.getDate（）+parseInt（day缺席））；
var dd=myDate.getDate（）；
var mm=myDate.getMonth（）+1；//一月是0！
var yyyy=myDate.getFullYear（）；
如果（dd<10）{dd='0'+dd}如果（mm<10）{mm='0'+mm}
var today=dd+'/'+mm+'/'+yyyy；
document.getElementById（“”）.value=today；
警报（今日）；
}    

这正是工作正常。。！！！谢谢..但问题是，当我在txtDurationTo.Text中设置后尝试获取值时，它给我的是mm/dd/yyyy格式。