Parse data and time string to Access Date value
How can I parse a date/time string into an Access Date object given a certain date- and time format?
I can use the CDate() function like this:
Dim StrDateTime As String
Dim DtTest As Date
StrDateTime = "2011-12-31 23:59:59"
DtTest = CDate(StrDateTime)
MsgBox DtTest
This works, Access recognizes the format, fine, but how can I absolutely be sure that this happens under all circumstances (e.g. Date/Time settings Regional Settings, Access version?). I would like to "tell" CDate my special date/time format.
Other option is this (but a lot of code):
Dim StrDateTime As String
Dim IntYear As Integer
Dim IntMonth As Integer
Dim IntDay As Integer
Dim IntHour As Integer
Dim IntMinute As Integer
Dim IntSecond As Integer
StrDateTime = "2011-12-31 23:59:59"
IntYear = Val(Mid(StrDateTime, 1, 4))
IntMonth = Val(Mid(StrDateTime, 6, 2))
IntDay = Val(Mid(StrDat开发者_高级运维eTime, 9, 2))
IntHour = Val(Mid(StrDateTime, 12, 2))
IntMinute = Val(Mid(StrDateTime, 15, 2))
IntSecond = Val(Mid(StrDateTime, 18, 2))
DtTest = DateSerial(IntYear, IntMonth, IntDay)
DtTest = DtTest + TimeSerial(IntHour, IntMinute, IntSecond)
MsgBox DtTest
Other advantage of CDate(): it give a Type Mismatch error on a wrong date/time value. DateSerial + TimeSerial recalculates a new date and time, so "2011-12-31 24:59:59" becomes 01/Jan/2012 0:59:59.
The format "yyyy-mm-dd" is an ISO standard and when encountering it, CDate()
expects the "yyyy" part to be followed by "mm-dd", never by "dd-mm". So a date string in that format is unambiguous; it represents the same date value regardless of the user's locale. And CDate()
will comply.
Furthermore, there is no way to give CDate()
a date string formatted as "yyyy-dd-mm" and get the date value you intend back. So CDate("2011-02-01")
will always give you the date value #Feb 1 2011#
(regardless of your locale), even if you intended that string to represent #Jan 2 2011#
. And CDate("2011-31-01")
will throw a type mismatch error.
Also note that this only works for dates after the year 100. (See Heinzi's comment.)
精彩评论