Android Question Date arithmetic: subtract days from current date

[TyneBridges]

I'm trying to do some simple date arithmetic in B4A but the logic of this defeats me, even with DateUtils loaded. All I want to do is subtract a given number of days from the current date and return the new date as a string.

I know I can get the current date using DateTime.Now and extract parts of it with DateTime.GetDayOfMonth(OurDate). I can see that Periods and SetDateAndTime might be able to do what I want but, without an example, I can't figure out the code for this.

Evidently I can't use a statement like OurStartDate = DateTime.Subtract(DateTime.Now, 375) because DateTime.Subtract is in Java but not B4A...?

I've searched on line because I thought the answer to this would be on line, but I can't find it. Maybe it's so simple that no-one else has asked, and I'm just dim. Is there a simple way to do this?

Thanks.

 

[imbault]

OurStartDate = DateTime.Add(DateTime.Now, 0, 0, -nDays)

 

[TyneBridges]

Thanks imbault - that's great. I had searched the documentation and missed that, although "Subtract" isn't valid, "Add" is.

A supplementary query - although my date variables are declared as strings and I precede the assignation statement with DateTime.DateFormat = "yyyy-MM-dd", the dates aren't returned in the expected format, but as long numbers. I've obviously missed how to tell B4A that the string contents are dates...

 

[TyneBridges]

Sorry, got it - the syntax is convoluted but it's (e.g.) StartDt = DateTime.Date(DateTime.Add(DateTime.Now, 0, 0, -375))

 

[inakigarm]

Have you seen Date Utils (AddPeriod) ?

 

[Erel]

You should use DateUtils.AddPeriod.