Isdate

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IsDate

Returns true if the text can be read as a date in the system's date format.

Syntax

Declare Function IsDate ( ByRef stringdate As Const String ) As Long

Parameters

• stringdate

Description

Date strings must be in the format set in the regional settings of the OS to be considered valid dates.

IsDate(Date) will return non-zero (-1) only if the regional settings specify the same date format that QB used.

The compiler will not recognize this function unless vbcompat.bi or datetime.bi is included.

Return Value

Returns non-zero (-1) if the date string can be converted to a Date Serial, otherwise returns zero (0).

Remarks

Usage

#include "vbcompat.bi"

result = IsDate( stringdate )

Differences from QB

• New to FreeBASIC

See also

• DateSerial
• TimeValue
• DateValue

Examples

#include "vbcompat.bi"

Dim s As String, d As Long

Do

  Print

  Print "Enter a date: "

  Line Input s

  If s = "" Then Exit Do

  If IsDate( s ) = 0 Then

    Print "'"; s; "' is not a valid date"

  Else

    d = DateValue( s )

    Print "year  = "; Year( d )

    Print "month = "; Month( d )

    Print "day   = "; Day( d )

  End If

Loop

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Category: Date and Time Functions
Kind: function

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Reproduced from the FreeBASIC Wiki Manual under the GNU Free Documentation License 1.3 — with no Invariant Sections, no Front-Cover Texts and no Back-Cover Texts. Copyright © the FreeBASIC project and wiki contributors. See License.