Calculating a Subtotal for Shopping Cart

[Sparky Arbuckle]

I'm trying to calculate the subtotal for each item the customer has in
the shopping cart. objDataReader(" decPrice") is the price from my
database field called decPrice. The .8 is for a 20% discount. The
error I get is:

Compiler Error Message: BC30201: Expression expected.

What is the correct syntax for this operation? When I check the
compiler output there is a ~ underneath the &. Any help would be
greatly appreciated.

<!-- CODE SNIPPET -->

Dim strSubTotal as string = 0
Dim i as integer = 0
FOR i = 0 to gtCart.count -1
dim strItemID as string = ds.Tables("tblS Cart").rows(i)( "ItemID")
ds.Tables("tblS Cart").rows(i)( "Qty") = gtCart(strItemI D)
strSubTotal = .8 * & objDataReader(" decPrice")
NEXT

<!-- CODE SNIPPET -->

[Ken Dopierala Jr.]

Hi,

Try this:

strSubTotal = CStr(.8 * CDec(objDataRea der("decPrice") ))

Good luck! Ken.

--
Ken Dopierala Jr.
For great ASP.Net web hosting try:
http://www.webhost4life.com/default.asp?refid=Spinlight
If you sign up under me and need help, email me.

"Sparky Arbuckle" <tw*@secureroot .com> wrote in message
news:11******** **************@ o13g2000cwo.goo glegroups.com.. .

I'm trying to calculate the subtotal for each item the customer has in
the shopping cart. objDataReader(" decPrice") is the price from my
database field called decPrice. The .8 is for a 20% discount. The
error I get is:

Compiler Error Message: BC30201: Expression expected.

What is the correct syntax for this operation? When I check the
compiler output there is a ~ underneath the &. Any help would be
greatly appreciated.

<!-- CODE SNIPPET -->

Dim strSubTotal as string = 0
Dim i as integer = 0
FOR i = 0 to gtCart.count -1
dim strItemID as string = ds.Tables("tblS Cart").rows(i)( "ItemID")
ds.Tables("tblS Cart").rows(i)( "Qty") = gtCart(strItemI D)
strSubTotal = .8 * & objDataReader(" decPrice")
NEXT

<!-- CODE SNIPPET -->

[gaidar]

The error is here:

strSubTotal = .8 * & objDataReader(" decPrice")

If you want to add ".8 *" as string do it in the following way:

strSubTotal = ".8 *" & objDataReader(" decPrice")

But if you want to multiply the value of objDataReader(" decPrice") by .8 and
then convert the value to string

strSubTotal = CType(0.8 * CType(objDataRe ader("decPrice" ), Double), string)
Best regards,

Gaidar
"Sparky Arbuckle" <tw*@secureroot .com> wrote in message
news:11******** **************@ o13g2000cwo.goo glegroups.com.. .

I'm trying to calculate the subtotal for each item the customer has in
the shopping cart. objDataReader(" decPrice") is the price from my
database field called decPrice. The .8 is for a 20% discount. The
error I get is:

Compiler Error Message: BC30201: Expression expected.

What is the correct syntax for this operation? When I check the
compiler output there is a ~ underneath the &. Any help would be
greatly appreciated.

<!-- CODE SNIPPET -->

Dim strSubTotal as string = 0
Dim i as integer = 0
FOR i = 0 to gtCart.count -1
dim strItemID as string = ds.Tables("tblS Cart").rows(i)( "ItemID")
ds.Tables("tblS Cart").rows(i)( "Qty") = gtCart(strItemI D)
strSubTotal = .8 * & objDataReader(" decPrice")
NEXT

<!-- CODE SNIPPET -->

[Sparky Arbuckle]

Thanks for the prompt reply Ken. Now I get a new error:

Exception Details: System.NullRefe renceException: Object reference not
set to an instance of an object.

[Sparky Arbuckle]

Gaidar:

I get the same error when I try your example. Maybe more insight would
be had if I were to tell the group that I am binding this information
to a dataGrid?

[gaidar]

May be you will post complete code of the class?

"Sparky Arbuckle" <tw*@secureroot .com> wrote in message
news:11******** **************@ g14g2000cwa.goo glegroups.com.. .

Gaidar:

I get the same error when I try your example. Maybe more insight would
be had if I were to tell the group that I am binding this information
to a dataGrid?

[Sparky Arbuckle]

You got it:

Sub UpdateCookie(by Ref gtCart as HashTable)

'Retrieve querystring parameters
Dim strDelete as string = Request.queryst ring("Delete")
Dim strAdd as string = Request.queryst ring("Add")

'If no changes to cookie then return
IF strDelete < " " and strAdd < " " THEN RETURN

IF strDelete > " " THEN
IF gtcart.Contains (strDelete) THEN
IF gtCart(strDelet e) = 1 THEN
gtCart.remove(s trDelete)
ELSE
gtCart(strDelet e) = gtCart(strDelet e)-1
END IF
ELSE
Response.Write( "No such ASIN in cart: " & strDelete & "<br>")
RETURN
END IF
END IF

IF strAdd > " " THEN
IF gtCart.Contains (strAdd) THEN
gtCart(strAdd) = gtcart(strAdd) + 1
ELSE
gtCart(strAdd) = 1
END IF
END IF

'Delete cookie if empty. This eliminates empty "ghost" key.
IF gtCart.count = 0 THEN
Response.Cookie s(MyCookieName) .Expires = Now.AddDays(-1)
RETURN
END IF

'Write HashTable back to cookie
Dim MyCookie as new httpCookie(MyCo okieName)

Dim iCount as integer = 0
Dim objConn as new
OLEDBConnection (ConfigurationS ettings.AppSett ings("StrConnec tion"))
Dim strSQL as string = "SELECT ASIN, strTitle, strArtist, decPrice,
strLabel, intNumberDisks, dtReleaseDate, strReview, strImageDir " & _
"FROM tblDescription WHERE "

FOR EACH myItem as DictionaryEntry in gtCart
iCount = iCount + 1
MyCookie.Values (myItem.Key) = myItem.Value

strSQL += "ASIN= '" & myItem.Key & "'"

IF iCount < gtCart.Count
strSQL += " OR "

ELSE

strSQL += ";"
END IF

Response.Cookie s("Customer")(" Quantity") = MyItem.Value

NEXT

Dim objDataReader as OLEDBDataReader
objConn.Open()

Dim objCommand as new OLEDBCommand(st rSQL,objConn)

Dim myCommand as new OleDbDataAdapte r(strSQL, objConn)
myCommand.Fill( ds, "tblSCart")
ds.Tables("tblS Cart").Columns. Add("Qty")

Dim strSubTotal as string = 0
Dim i as integer = 0
FOR i = 0 to gtCart.count -1
dim strASIN as string =
ds.Tables("tblS Cart").rows(i)( "ASIN")
ds.Tables("tblS Cart").rows(i)( "Qty") = gtCart(strASIN)
strSubTotal = ".8 *" & objDataReader(" decPrice")
NEXT

lblShipping.tex t = 0
lblSubTotal.tex t = strSubTotal
lblGrandTotal.t ext = 0

dgSCart.DataSou rce = ds.Tables("tblS cart").DefaultV iew
dgSCart.DataBin d()

'Write cookie to page
Response.Cookie s.Add(MyCookie)
Response.Cookie s(MyCookieName) .Expires = Now.AddDays(30)

FOR EACH myItem as DictionaryEntry in gtCart
MyCookie.Values (myItem.Key) = myItem.Value

NEXT

END Sub