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VBScript The DateSerial Function

The DateSerial function returns a Variant of subtype Date for a specified year, month, and day.

DateSerial(year,month,day)

Parameter	Description
year	Required. A number between 100 and 9999, or a numeric expression. Values between 0 and 99 are interpreted as the years 1900–1999. For all other year arguments, use a complete four-digit year
month	Required. Any numeric expression
day	Required. Any numeric expression

document.write(DateSerial(1996,2,3) & "<br />")
document.write(DateSerial(1990-20,9-2,1-1))

Output:

2/3/1996
6/30/1970