Date handling using Javascript

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1

Hi guys. I am trying to create a runtime property that returns a date 10 days prior to today.
The approach I have been using, is to create a DateTime runtime property and added a function to it:
return getDateDaysAgo(10);

function getDateDaysAgo(days) {
const date = new Date();
date.setDate(date.getDate() - days);
return date;
}

When I check the value, it returns “undefined”. It seems that the datatype returned from the function is incompatible with the DataTime datatype on the runtime property.
The reason I need this, is to be able to use the value in a filter on a datasource in our application.

Please advise on a better approach. Any feedback is appreciated :slight_smile:
Øystein

2

Hi

You need to convert the date to an ISOstring when you’re done with all date handling, so that Appfarm can read it.

function getDateDaysAgo(days) {
    const date = new Date();
    date.setDate(date.getDate() - days);
    return date;
}

return getDateDaysAgo(10).toJSON()

You can also use Moment in Create if you prefer: Date and time | Appfarm Documentation

// Erik

3

Excellent. That seems to do the trick :slight_smile:
Thank you.

Øystein

4

Hi!

Just an additional comment on this one!

If you have not used the Value processor for the purpose of adding/subtracting time units from a datatime, please check out this article. E.g. for your case, you may set the date to Now and then apply a Value processor subtracting 10 days.

5

Hi again and thank you for the update. As I understand it, this approach works well for visual presentations of a date. Is it also possible to use it for evaluations like in IF statements?