Javascript - Add business days to a user selected date

问题

I need to add user defined business days to a user defined date and for it to display in an alert box.

Could you please look at my code and let me know what needs changing:

See JSFiddle

Select Business Days To Add<br>
<select name="coll" id="t1">
<option value="1">1</option>
<option value="2">2</option>
<option value="3">3</option>
</select><p>

  <script src="http://code.jquery.com/ui/1.10.3/jquery-ui.js"></script>
    <script>  $(function() {    $( "#datepicker" ).datepicker(); }); </script>

<input id="datepicker" onchange="alert()"/>

回答1:

For a start write a function that takes the selected date and days:

<center>Select Business Days To Add<br>
<select name="coll" id="t1">
<option value="1">1</option>
<option value="2">2</option>
<option value="3">3</option>
</select><p>

  <script src="http://code.jquery.com/ui/1.10.3/jquery-ui.js"></script>
    <script>  $(function() {    $( "#datepicker" ).datepicker(); });
    function getSelectedDate() {
           var day = $("#datepicker").datepicker("getDate");     
           var daysToAdd = $("#t1").val();
           return Number(daysToAdd) + Number(day.getDate());
        }
    </script>

<input id="datepicker" onchange="alert(getSelectedDate());"/>

I suppose business days mean from monday to friday, so adding 1 to friday would mean actually monday and not saturday.

Further

you need to look if the current day is friday and add two days to the selected business days to jump over the weekend - use getDate()
if it is end of the month (regarding even and uneven months 30 and 31 days and february on leap and not leap year) and if needed increment the month too - use getMonth
if it is end of the year, increment the year - use getFullYear

The code (without the check for weekends) looks like this:

<center>Select Business Days To Add<br>
<select name="coll" id="t1">
<option value="1">1</option>
<option value="2">2</option>
<option value="3">3</option>
</select><p>

  <script src="http://code.jquery.com/ui/1.10.3/jquery-ui.js"></script>
    <script>  $(function() {    $( "#datepicker" ).datepicker(); });

        function isEndOfMonth(date) {
        // day of month from 1 to 31
        var selectedDay = date.getDate();
        // months with 31 days
        if (date.getMonth() == 0 || date.getMonth() == 2 || 
            date.getMonth() == 4 || date.getMonth() == 6 || 
            date.getMonth() == 7 || date.getMonth() == 9 || 
            date.getMonth() == 11) {
            return selectedDay == 31;
        }
        // february 28 / 29 days TODO check for leap year!
        if (date.getMonth() == 1) { return selectedDay == 28; }

        // months with 30 days
        if (date.getMonth() == 3 || date.getMonth() == 5 || 
            date.getMonth() == 8 || date.getMonth() == 10) {
            return selectedDay == 30;
        }
            return false;
        }

        function isEndOfYear(month) {
            return month > 11;
        }

        function getSelectedDate() {
           var day = $("#datepicker").datepicker("getDate");

           var daysToAdd = Number($("#t1").val());
           // values from which the new date is constructed
           var selectedMonth = day.getMonth();
           var selectedYear = day.getFullYear();
           var selectedDay = day.getDate();
           // 
           if (isEndOfMonth(day)) {
               // start new month
               selectedDay = 1;
               selectedMonth++;
               if (isEndOfYear(selectedMonth)) {
                   // start new year
                   selectedYear++;
               }
           }
            // add business days
            selectedDay += daysToAdd;
            // TODO check if the result is weekend and jump over it. After a jump the same checks as above should be called!
            return new Date(selectedYear, selectedMonth, selectedDay, 0, 0, 0, 0);
        }
    </script>

<input id="datepicker" onchange="alert(getSelectedDate());"/>

If for example the selected date is 14.Oct.2013, selected days 2, the function yields 16.Oct.2013.

来源：https://stackoverflow.com/questions/19282371/javascript-add-business-days-to-a-user-selected-date

标签

javascript

datepicker