Date variable problem

drbbton · October 29th, 2003, 03:54 PM

I am having a very stupid problem. Below is the snippet that i have been testing with. My problem is that when the "expiredate" is defined as a variable then inserted into the if statment it doesnt read its value. It always says that it has not expired. Example:

thedate = date
expiredate = "08/03/2003"
if thedate < expiredate then
response.write "Not Expired"
else
response.write "You have Expired"
end if

''this would return "Not Expired"

Now if I remove the variable and directly insert the date, it works! Example:

thedate = date
if thedate < "08/03/2003" then
response.write "Not Expired"
else
response.write "You have Expired"
end if

''this would return "You Have Expired"

I have to use a variable with the form i am creating. Does anyone know why this happens, or if there would be a work around? Thanks

Imar · October 29th, 2003, 05:17 PM

Hmmm, this *is* a stupid problem. I think what happens is that ASP under the hood creates a string type for the expiredate variable, but that it sees it as a "real" date when you compare it directly with another date. It has always been unclear to me how ASP deals with variants that have some underlying value.

Anyway, you can fix it by "casting" the expiredate to a date, using the DateValue method. This will work:

Code:

thedate = Date()
expiredate = DateValue("08/03/2003")
If thedate < expiredate Then
    Response.Write("Not Expired")
Else
    Response.Write("You have Expired")
End If

HtH,

Imar

---------------------------------------
Imar Spaanjaars
Everyone is unique, except for me.

KenSchaefer · October 30th, 2003, 03:12 AM

VBScript doesn't have any types except a Variant, which in turn can have subtypes. If you do myDate = "01/01/2003" then the subtype will probaby be "text", and then when you compare it to a subtype "date", one or the other needs to cast to the other type. If your date subtype is cast to a string, and compared to your initial string, then you may get results other than what you expect.

To be safe, cast the variant of subtype string to subtype date using CDate()

Cheers
Ken

Microsoft MVP - Windows Server (IIS)
www.adOpenStatic.com

DaveGerard · October 30th, 2003, 11:53 AM

Here you go.

<%
thedate = date()
expiredate = "08/03/2003"
if cDate(thedate) < cDate(expiredate) then
response.write "Not Expired"
else
response.write "You have Expired"
end if
%>