Confused with the type mismatch error

[Bob Barrows]

I tried your simple example and got no type mismatch. I even modified it so
that I was comparing a string to a number and got no type mismatch (it
returns "Not Equal", but that's to be expected when comparing a string to a
number):
dim a, b
a = "123456"
b = a
a = clng(123456)
if a <> b Then
Response.Write "Not equal"
else
Response.Write "Equal"
end if

I cannot venture a guess as to the cause of your mismatch: perhaps you need
to initialize the PreviousOne variable with a value before starting the
loop.

I question why you think being forced to explicitly cast your variables
using CStr is a "bad" thing ... I know you're not saying it's "bad": you're
simply asking why you have to do it in this case. My suggestion would be to
make it a habit: something you do more often than not, instead of only when
you have to.

Bob Barrows


cschang wrote:

> Why a variable assigned as '123456' can be mismatched with another
> variable also assign as '123456' in the following example
> dim a, b
> a = '123456'
> b = a
> a = '123456'
> if a <> b Then
> ....
>
> ASP engine return an error " Type mismatch" for a <> b. I had to
> apply Cstr() to both a and b to compare, otherwise it always generates
> the same error, even only the Cstr() on one side of the comparison.
>
> The part of the real codes of my page
>
> Dim previousOne, rowControl
> rowControl = 0
>
> while not rs.EOF and rowControl < rs.PageSize
> If Not isEmpty(previousOne) Then
> If Cstr(previousOne) <> Cstr(rs(1)) Then
> Response.Write ...
> End If
> end If
> Response.Write ...
> ..
> previousOne = rs(1)
> rs.MoveNext
> rowControl = rowControl + 1
> Wend
>
> ' rs is the recordSet return from Oracle procdure. The specific
> record is defined as varchar in database.
>
> CS

[Ray at]

Perhaps this is another one of those situations where the value from the
recordset is null.

<%
Dim x
x = null
y = null
If x = y Then
response.write "Yes, null = null."
Else
response.write "No, null <> null."
End If

response.write "<br>"

x = x & ""
y = y & ""
If x = y Then
response.write "Yes, null+"""" = null+""""."
Else
response.write "No, null+"""" <> null+""""."
End If

%>

Ray at home

"Bob Barrows" <reb_01501@yahoo.com> wrote in message
news:OifORfNXDHA.2576@TK2MSFTNGP09.phx.gbl...

> I tried your simple example and got no type mismatch. I even modified it

so

> that I was comparing a string to a number and got no type mismatch (it
> returns "Not Equal", but that's to be expected when comparing a string to

a

> number):
>

> >
> > ASP engine return an error " Type mismatch" for a <> b. I had to
> > apply Cstr() to both a and b to compare, otherwise it always generates
> > the same error, even only the Cstr() on one side of the comparison.

[Dave Anderson]

"cschang" wrote:

>
> while not rs.EOF and rowControl < rs.PageSize
> If Not isEmpty(previousOne) Then
> If Cstr(previousOne) <> Cstr(rs(1)) Then
> Response.Write ...
> End If
> end If
> Response.Write ...
> ..
> previousOne = rs(1)
> rs.MoveNext
> rowControl = rowControl + 1
> Wend

Welcome to Default Property Hell. Your problem stems from your mistaken
belief that rs(1) is a value. It is an object with the default property
[Value]. To get around your problem, stop using default properties. The
correct syntax in this case (Assuming an ADODB.Recordset):

previousOne = rs.Fields(1).Value



--
Dave Anderson

Unsolicited commercial email will be read at a cost of $500 per message. Use
of this email address implies consent to these terms. Please do not contact
me directly or ask me to contact you directly for assistance. If your
question is worth asking, it's worth posting.

[cschang]

Dave:
You are perfectly right. I tested and found out in my case, all I had to do
was to use previousOne <> rs(1).value and the problem went away. Thank very
much.

C Chang

Dave Anderson wrote:

> "cschang" wrote:

> >
> > while not rs.EOF and rowControl < rs.PageSize
> > If Not isEmpty(previousOne) Then
> > If Cstr(previousOne) <> Cstr(rs(1)) Then
> > Response.Write ...
> > End If
> > end If
> > Response.Write ...
> > ..
> > previousOne = rs(1)
> > rs.MoveNext
> > rowControl = rowControl + 1
> > Wend

>
> Welcome to Default Property Hell. Your problem stems from your mistaken
> belief that rs(1) is a value. It is an object with the default property
> [Value]. To get around your problem, stop using default properties. The
> correct syntax in this case (Assuming an ADODB.Recordset):
>
> previousOne = rs.Fields(1).Value
>
> --
> Dave Anderson
>
> Unsolicited commercial email will be read at a cost of $500 per message. Use
> of this email address implies consent to these terms. Please do not contact
> me directly or ask me to contact you directly for assistance. If your
> question is worth asking, it's worth posting.