VB.NET Language in a Nutshell, Second Edition

Name

CDate Function

Named Arguments

No

Syntax

CDate(expression)

expression (required; String or Numeric)

Any valid representation of a date and time

Return Value

expression converted into a Date data type

Description

Converts expression to a Date data type.

The format of expression — the order of day, month, and year — is determined by the locale setting of the local computer. To be certain a date is recognized correctly by CDate, the month, day, and year elements of expression must be in the same sequence as the local computer’s regional settings; otherwise, the CDate function has no idea, for example, that 4 was supposed to be the fourth day of the month, not the month of April.

Rules at a Glance

• You can use any of the date delimiters specified in your computer’s regional settings; for most systems, this includes ,, /, -, and .

• The earliest date that can be handled by the Date data type is 01/01/100. The latest date that can be handled by the Date data type is 12/31/9999.

Programming Tips and Gotchas

• Use the IsDate function to determine if expression can be converted to a date or time.

• If you pass an empty string to CDate, an error is generated.

• A modicum of intelligence has been built into the CDate function. It can determine the day and month from a string, regardless of their position in the string; this applies only where the day number is larger than 12, which automatically distinguishes it from the number of the month. For example, if the string “30/12/97” is passed into the CDate ...