Weekday Function (Visual Basic)

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11/18/2006

Returns an Integer value containing a number representing the day of the week.

Public Function Weekday( _
   ByVal DateValue As DateTime, _
   Optional ByVal DayOfWeek As FirstDayOfWeek = FirstDayOfWeek.Sunday _
) As Integer

Parameters

DateValue
Required. Date value for which you want to determine the day of the week.

DayOfWeek
Optional. A value chosen from the FirstDayOfWeek enumeration that specifies the first day of the week. If not specified, FirstDayOfWeek.Sunday is used.

Settings

The DayOfWeek argument can have one of the following settings.

Enumeration value	Value	Description
FirstDayOfWeek.System	0	First day of week specified in system settings
FirstDayOfWeek.Sunday	1	Sunday (default)
FirstDayOfWeek.Monday	2	Monday (complies with ISO standard 8601, section 3.17)
FirstDayOfWeek.Tuesday	3	Tuesday
FirstDayOfWeek.Wednesday	4	Wednesday
FirstDayOfWeek.Thursday	5	Thursday
FirstDayOfWeek.Friday	6	Friday
FirstDayOfWeek.Saturday	7	Saturday

Exceptions

Exception type	Error number	Condition
ArgumentException	5	DayOfWeek is less than 0 or more than 7.

See the "Error number" column if you are upgrading Visual Basic 6.0 applications that use unstructured error handling. (You can compare the error number against the Number Property (Err Object).) However, when possible, you should consider replacing such error control with Structured Exception Handling Overview for Visual Basic.

Remarks

The value returned by the Weekday function corresponds to the values of the FirstDayOfWeek enumeration; that is, 1 indicates Sunday and 7 indicates Saturday.

Note

Weekday uses the current calendar setting from the CurrentCulture property of the CultureInfo class in the System.Globalization namespace. The default CurrentCulture values are determined by Control Panel settings.

Example

The following example uses the Weekday function to obtain the day of the week from a specified date.

Dim oldDate As Date
Dim oldWeekDay As Integer
oldDate = #2/12/1969#
oldWeekDay = Weekday(oldDate)
' oldWeekDay now contains 4 because thisDate represents a Wednesday.

Requirements

Namespace: Microsoft.VisualBasic

Module: DateAndTime

Assembly: Visual Basic Runtime Library (in Microsoft.VisualBasic.dll)

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