Diff is not a function in Moment.js

问题:

I am selecting a date in the Air Datepicker and trying to compare today's date to the selected date to determine the difference in days. So, for example, if today is 12/11/2016 and I select 12/20/2016, I want to get the difference, which is 9.

I keep running into the following error: "end.diff is not a function".

I've stripped the following code down to the essentials:

HTML

<form>     <input id="datereq" name="datereq" type="text" class="dateReq" value="" /> </form> <div id="selected"></div> 

JQUERY

 var date = new Date(),      disabledDays = [0, 6];   $('.dateReq').datepicker({      dateFormat: 'mm/dd/yyyy',      minDate: new Date(),      language: 'en',      autoClose: true,      onRenderCell: function(date, cellType) {          if (cellType == 'day') {              var day = date.getDay(),                  isDisabled = disabledDays.indexOf(day) != -1;              return {                  disabled: isDisabled              };          }      },       // Display Appropriate Order Type Options      onSelect: function onSelect(fd, date) {          var now = moment(new Date()).format('MM/DD/YYYY'),              end = fd,              days = end.diff(now, 'days');          $('#selected').html('now:' + now + 'end:' + end + 'diff:' + days);          //console.log('end:' + end);          //console.log('diff:' + days);      }  }); 

Fiddle

https://jsfiddle.net/qn530dpq/

回答1:

the first argument of the onSelect function is the date as text - not a moment object. Try to call the diff function on a moment object representing the selected date and it will work. Also you'll have to specify the variable "end" which is probably your "fd". Check it out: https://jsfiddle.net/t9suf65p/

    // Initialize Datepicker     var date = new Date(),     disabledDays = [0, 6];      $('.dateReq').datepicker({         dateFormat: 'mm/dd/yyyy',                 minDate: new Date(),         language: 'en',         autoClose: true,         onRenderCell: function (date, cellType) {             if (cellType == 'day') {                 var day = date.getDay(),                     isDisabled = disabledDays.indexOf(day) != -1;                 return {                     disabled: isDisabled                 };             }         },          // Display Appropriate Order Type Options        onSelect: function onSelect(fd, date) {            var selectedDate = moment(fd, 'MM/DD/YYYY');            var now = moment(new Date());            var days = selectedDate.diff(now, 'days');                 $('#selected').html('now: ' + now.format('MM/DD/YYYY') +  'end: ' + selectedDate.format('MM/DD/YYYY') + ' diff: ' + days);                 //console.log('end:' + end);                 //console.log('diff:' + days);         }     }); 

回答2:

The diff function is only available on moment objects. Try this instead:

var now = moment(new Date()), end = moment(fd), days = end.diff(now, 'days'); 

回答3:

You can use something like this:

$('#datepickerId').datepicker({     onSelect: function() {         var date = $(this).datepicker('getDate');         var today = new Date();         var dayDiff = Math.ceil((today - date) / (1000 * 60 * 60 * 24));     } }); 

文章来源: Diff is not a function in Moment.js