Type mismatch: '[string: ""]'

[exsuscito]

After about 30 minutes of frustration I finally discovered what was
causing a general 500 internal server error and to my surprise it was
something I seem to always take for granted for its simplicity. A type
mismatch error trying to compare a string to a numerical value, which
is something that PHP has no problem or qualms with. However, this
continuous problem continues to haunt me year after year and has
brought me to tears with frustration. This is the line that raises the
error:

nID = Request("ID")
If IsNull(nID) Or IsEmpty(nID) Or nID = 0 Then
.... (and so on)

In the past I've written a function 30 lines long that compares values
by confirming value types of the variables first, but I would rather
put a gun to my head than do that. Since there are obviously other
bright PHP and ASP developers out there that constantly trip over this
problem, I would like to know your suggestions or methods of working
around this.

 

[Steven Burn]

First, don't use Request("item")... be explicit (i.e. Request.Form or
Request.Querystring or Request.ServerVariables)

nID = Request("ID")
If CStr(nID) <> "" And Len(Trim(CStr(nID))) > 0 Then
..... carry on

Example:

Empty: http://mysteryfcm.plus.com/misc/nid.asp?nid=
Null: http://mysteryfcm.plus.com/misc/nid.asp?nid=
Neither: http://mysteryfcm.plus.com/misc/nid.asp?nid=123

--
Regards

Steven Burn
Ur I.T. Mate Group
www.it-mate.co.uk

Keeping it FREE!

 

[Kyle Peterson]

read the 1st part of this article so you see the real errors... that will
help a shitload

http://www.powerasp.com/content/hintstips/common_sense.asp