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Strings.FormatDateTime Method

Returns a string expression representing a date/time value.

Namespace:  Microsoft.VisualBasic
Assembly:  Microsoft.VisualBasic (in Microsoft.VisualBasic.dll)

static member FormatDateTime : 
        Expression:DateTime * 
        NamedFormat:DateFormat -> string 


Type: System.DateTime
Required. Date expression to be formatted.
Type: Microsoft.VisualBasic.DateFormat
Optional. Numeric value that indicates the date/time format used. If omitted, DateFormat.GeneralDate is used.

Return Value

Type: System.String
Returns a string expression representing a date/time value.


NamedFormat setting is not valid.

The Date data type always contains both date and time information. For purposes of type conversion, Visual Basic considers 1/1/1 (January 1 of the year 1) to be a neutral value for the date, and 00:00:00 (midnight) to be a neutral value for the time. If you format a Date value as a date/time string, FormatDateTime does not include neutral values in the resulting string. For example, if you convert #1/1/0001 9:30:00# to a string, the result is "9:30:00 AM"; the date information is suppressed. However, the date information is still present in the original Date value and can be recovered with functions such as DatePart.


If you pass the Expression argument as a String literal, FormatDateTime interprets it according to the CurrentCulture setting of your application. However, if you pass it as a Date literal, use the format #mm/dd/yyyy#, because FormatDateTime always interprets a Date literal according to the English (US) culture. This is necessary because, if an application is developed and coded using Date literals from one culture, but is then executed on a platform with a different culture, the Date literals could be parsed incorrectly.

The NamedFormat argument has the following settings.




Display a date and/or time. Display a date part as a short date. If there is a time part, display it as a long time. If present, both parts display.


Display a date using the long date format specified in your computer's regional settings.


Display a date using the short date format specified in your computer's regional settings.


Display a time using the time format specified in your computer's regional settings.


Display a time using the 24-hour format (hh:mm).

This example demonstrates the use of the FormatDateTime function.

' English (US) format.
Dim TestDate As DateTime = #3/12/1999#

' FormatDateTime returns "Friday, March 12, 1999".
' The time information is neutral (00:00:00) and therefore suppressed.
Dim TestString As String = FormatDateTime(TestDate, DateFormat.LongDate)

.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.