如何使用jQuery添加日期

Question

I have input text like below:

 $('#term').change(function() { var ll = $(this).val(); var bb = $('#date').val(); var date = new Date(bb); var newDate = new Date(date); newDate.setDate(newDate.getDate() + parseInt(ll)); var dd = newDate.getDate(); var mm = newDate.getMonth() + 1; var y = newDate.getFullYear(); var someFormattedDate = dd + '-' + mm + '-' + y; $('#due_date').val(someFormattedDate); }); 

 div { margin: 10px; } 

 <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> <div class="form-group"> <label for="date">Date:</label> <input id="invodate" type="text" id="date" class="form-control" name="date" value="" style="width: 150px;"> </div> <div class="form-group"> <label for="term">Term:</label> <input type="text" class="form-control" id="term" name="term" value="" style="width: 50px;"> </div> <div class="form-group"> <label for="due_date">Due Date:</label> <input type="text" class="form-control" id="due_date" name="due_date" value="" style="width: 150px;"> </div> 

I wanna give days to input #term and then on Due Date in input show date, but in my code show NaN-NaN-NaN only. What error with my code. thank for answer.

Answer 1

Your first input has two ID's, which is invalid, and you're passing a date object to the Date constructor.

This is quite simple with plain javascript

 $('#term').change(function() { var ll = $(this).val(); var bb = $('#date').val(); var date = new Date(bb); date.setDate(date.getDate() + (+ll)); var dd = date.getDate(); var mm = date.getMonth() + 1; var y = date.getFullYear(); var someFormattedDate = dd + '-' + mm + '-' + y; $('#due_date').val(someFormattedDate); }); 

 <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> <div class="form-group"> <label for="date">Date:</label> <input type="text" id="date" class="form-control" name="date" value="05-05-2017" style="width: 150px;"> </div> <div class="form-group"> <label for="term">Term:</label> <input type="text" class="form-control" id="term" name="term" value="" placeholder="type here" style="width: 50px;"> </div> <div class="form-group"> <label for="due_date">Due Date:</label> <input type="text" class="form-control" id="due_date" name="due_date" value="" style="width: 150px;"> </div> 

Answer 2

Nan (Not a number) getDate function does not return integer. Object + 11 is not a valid operation (most of the time!).

You can use Datejs mentioned here

var duedate = new Date.today().addDays(11);