Check if a date within in range

问题:

I am trying to check if a date of format mm.dd.yyyy is greater than today and less than the date after 6 months from today.

Here is my code:

var isLinkExpiryDateWithinRange = function(value) {
    var monthfield = value.split('.')[0];
    var dayfield = value.split('.')[1];
    var yearfield = value.split('.')[2];
    var inputDate = new Date(yearfield, monthfield - 1, dayfield);
    var today = new Date();     
    today = new Date(today.getFullYear(), today.getMonth(), today.getDate());
    alert(inputDate > today);//alert-> true
    var endDate = today;
    endDate.setMonth(endDate.getMonth() + 6);
    alert(inputDate > today);//alert-> false
    if(inputDate > today && inputDate < endDate) {
        alert('1');
    } else {
        alert('2');/always alert it
    }
}

If I execute isLinkExpiryDateWithinRange('12.08.2012') I wish it will show 1 as this is within the range, but it is displaying 2. Moreover the first alert is showing true and the second one false.

Can anyone please explain what is happening?

回答1:

Change:

var endDate = today;

to:

var endDate = new Date(today);

See the posts here for how objects are referenced and changed. There are some really good examples that help explain the issue, notably:

Instead, the situation is that the item passed in is passed by value. But the item that is passed by value is itself a reference.

JSFiddle example

回答2:

function isLinkExpiryDateWithinRange( value ) {
    // format: mm.dd.yyyy;
    value = value.split(".");
    var todayDate = new Date(),
        endDate = new Date( todayDate.getFullYear(), todayDate.getMonth() + 6, todayDate.getDate() +1 );
        date = new Date(value[2], value[0]-1, value[1]);

    return todayDate < date && date < endDate;
}

isLinkExpiryDateWithinRange("12.24.2012"); // true
isLinkExpiryDateWithinRange("12.24.2020"); // false

回答3:

Below function checks if date selected is within 5 days from today. Date format used is "DD-MM-YYYY", you can use any format by changing value.split('-')[1] order and split character.

function showMessage() {
        var value = document.getElementById("invoiceDueDate").value;
        var inputDate = new Date(value.split('-')[2], value.split('-')[1] - 1, value.split('-')[0]);
        var endDate = new Date();
        endDate.setDate(endDate.getDate() + 5);// adding 5 days from today
        if(inputDate < endDate) {
            alert("If the due date selected for the invoice is within 5 days, and express settlement fee will apply to this transaction.");
        }

    }