Julian Date

I have bene told that the Julian date function will prevent a innvalid date from been entered, can somebody please post the procedur.

By an invalid date i mean liek 30th February
And to take into counf ot leap years

Thanks

I have bene told that the Julian date function will prevent a innvalid date from been entered, can somebody please post the procedur.

By an invalid date i mean liek 30th February
And to take into counf ot leap years

Thanks

The code I posted in thread
http://www.xtremevbtalk.com/showthread.php?p=896783#post896783

may be of interest (hope the link works) if not please come back

regards hugh

im not sure what the "Julian Date Fuction" is, and have always coded my own when i needed to get that value.

...anyway, IsDate() may help you out in this situation.

my immidiate window results

?isdate("02/28/2005")
True

?isdate("02/30/2005")
False

?isdate("x")
False

I want to valid a date so that an invalid date such as 30th February can not be entered, i was given thsi code about Julian date.


Private Sub Form_Load()
Dim i As Integer

' Sets the days in each month, for refrence
days(1) = 31
days(2) = 28
days(3) = 31
days(4) = 30
days(5) = 31
days(6) = 30
days(7) = 31
days(8) = 31
days(9) = 30
days(10) = 31
days(11) = 30
days(12) = 31

' Adds values to combo box
For i = 1 To 31 ' Adds days to combo box
cboDay.AddItem Str(i)
Next i

For i = 1 To 12 ' Adds months to combo box
cboMonth.AddItem Str(i)
Next i

For i = 1905 To 1990 ' Adds years to combo box
cboYear.AddItem Str(i)
Next i

End Sub

'Calculates the number of days in february
Function daysInMonth(m, y As Integer)
If m <> 2 Then ' Need to check leap year for Feb
daysInMonth = days(m)
Else
If leapYear(y) Then
daysInMonth = 29
Else
daysInMonth = 28
End If
End If
End Function

' Checks to see if year is a leap year
Function leapYear(y As Integer)
leapYear = (y Mod 4 = 0) And ((y Mod 100 <> 0) Or (y Mod 400 = 0))
End Function

Function dateName(dd, mm, yy As Integer)
Dim d, c, m, y As Integer
m = mm - 2 ' Sep = 7, Oct = 8 etc
If m < 1 Then
yy = yy Mod 100 ' get the 2 digits of year (03)
c = (yy - y) \ 100 ' get century
d = (Int(2.6 * m - 0.2) + dd + y + Int(y / 4) + Int(c \ 4) - (2 * c) + 700) Mod 7
dateName = dayname(d)
End Function


What i want to know is how do incoperate this whith an if statment when cmd_save is cliked, will it need another procedure?

As jjStinger72 mentioned, the IsDate function will work nicely:


If IsDate(dYourDate) Then
' Do something with the data
Else
' Prompt that the date was invalid.
End If


If you use seperate Day, Month and Year selections, you could use the DateSerial function to generate your date variable. DateSerial is also handy to get the number of days in a month, in order to populate a days dropdown list.


Function LastDateOfMonth(ByVal lMonth As Long, ByVal lYear As Long) As Long
LastDateOfMonth = Day(DateSerial(lYear, lMonth + 1, 0))
End Function


You could call that function when the Month dropdown selection is selected, in order to clear and repopulate the days.

I need to do it this way to show complexcity

I need to do it this way to show complexcity

Interesting.. so your plan is to take something very simple and make it overly complex?

Sounds like a class assignment...