VB.NET Language in a Nutshell, Second Edition

Name

DateValue Function

Class

Microsoft.VisualBasic.DateAndTime

Syntax

DateValue(stringdate)

stringdate (required; String)

A string containing any of the date formats recognized by IsDate

Return Value

A Date that represents the date specified by the stringdate argument

Description

Returns a Date containing the date represented by stringdate.

The date value is formatted according to the short date setting defined by the Regional Settings applet in the Control Panel. DateValue can successfully recognize a stringdate in any of the date formats recognized by IsDate. DateValue does not return time values in a date/time string; they are simply dropped. However, if stringdate includes a valid date value but an invalid time value, a runtime error results.

Rules at a Glance

• The order of the day, month, and year within stringdate must be the same as the sequence defined by the computer’s regional settings.

• Only those date separators recognized by IsDate can be used.

• If you don’t specify a year in your date expression, DateValue uses the current year from the computer’s system date.

Example

Dim sDateExpression As String

sDateExpression = 10 & "/" & "March" & "/" & 1998

If IsDate(sDateExpression) Then
    Console.WriteLine(DateValue(sDateExpression))
Else
    Console.WriteLine("invalid date")
End If

Programming Tips and Gotchas

• When working with dates, always check that a date is valid using the IsDate function prior to passing it as a function argument.

• If stringdate includes time information as well as date ...