Islapyear

[volvomann]

Hello.

Is ther an funtion lik this isleapyear(now.now) from "VB net" in B4a. I won`t to check i a year is leapyear?

 

[Erel]

Here:

Sub Activity_Create(FirstTime As Boolean)
   Log(IsLeapYear(2011))
   Log(IsLeapYear(2012))
End Sub

Sub IsLeapYear(Year As Int) As Boolean
   Dim df As String
   df = DateTime.DateFormat
   DateTime.DateFormat = "MM/dd/yyyy"
   Try
      DateTime.DateParse("02/29/" & Year)
      DateTime.DateFormat = df
      Return True
   Catch
      Return False
      DateTime.DateFormat = df
   End Try
End Sub

 

[Jost aus Soest]

This one is much faster:

Sub LeapYear(Year As Int) As Boolean
  If Year Mod 400 = 0 Then Return True
  If Year Mod 100 = 0 Then Return False
  If Year Mod 4 = 0 Then Return True
  Return False
End Sub

 

[volvomann]

I do not understand,
what do I test on (If LeapYear is= true then label1.text=" Leapyear")?

 

[Erel]

I agree that Jost's "white box" solution is better than my "black box" solution

To use it:

If LeapYear(2000) = True Then label1.Text = "LeapYear"

 

[Jost aus Soest]

what do I test on (If LeapYear is= true then label1.text=" Leapyear")?

I'm not sure that I really understand your question...
A LeapYear depends on a specific year, so you must give that information, e. g.:

If LeapYear(2012) Then Label1.Text = "Leapyear"

If you need this information for the current year, just use DateTime.GetYear(DateTime.Now) instead of 2012.

 

[Jost aus Soest]

I agree that Jost's "white box" solution is better than my "black box" solution

Thanks a lot!

BTW: If we had functional overloading, we could optionaly ommit the year-parameter to use "automagically" the current year instead...

 

[volvomann]

Thanks it works

 

[Jost aus Soest]

You are welcome!

 

[Ricky D]

If the year is divisible by 400 it is not a leap year.

The year 2000 wasn't a leap year

regards Ricky

 

[volvomann]

If the year is divisible by 400 it is not a leap year.

The year 2000 wasn't a leap year

regards Ricky

1600 2000 2400 is leapyear butt not 2100 2200 2300 because they can`t be divided by 400

 

[moster67]

1600 2000 2400 is leapyear butt not 2100 2200 2300 because they can`t be divided by 400

interesting reading....
but I think I will leave the verification of the years 2100, 2200, 2300 and 2400 to someone else

 

[Jost aus Soest]

Thr truth!

interesting reading....
but I think I will leave the verification of the years 2100, 2200, 2300 and 2400 to someone else

Ok, I'm someone else!

You can trust my source code ...
...or look into Wikipedia:
Leap year - Wikipedia, the free encyclopedia

All in all: It's true, 2000 was a leap year!

 

[moster67]

@jost...

I don't think you understood my stupid joke. I was referring to the dates - far too much in future for me still being around

 

[Jost aus Soest]

I was referring to the dates - far too much in future for me still being around

Now I got it! :sign0148: