How to test for null values using the dreamweaver datasets
Posted on 2004-10-01
I am using a dreamweaver dataset that has a query for totalling values in a database in a VB ASP.NET page. The code to display my total is (as placed by DWMX when you drag the field) :
<%# QryBasketTotal.FieldValue("TOTALAMOUNT", Container) %>
This displays the totals fine, but not formatted to 2 decimal places so I tried the following:
<%# formatCurrency(QryBasketTotal.FieldValue("TOTALAMOUNT", Container),2) %>
Which also works UNTIL the value of "TOTALAMOUNT" is empty or null, then it falls over in a big heap.
So, my question is, how can you test for a null value in ASP.NET on a dataset?
I have tried making my own functions to do a simple if <blah> is NULL then... but it would appear NULL is not supported, so I tried dbNull.Value (as found on the web):
function DisplayTotal() as String
if QryBasketItems.FieldValue("TOTALAMOUNT", Container) is dbNull.Value then
DisplayTotal =formatCurrency(QryBasketTotal.FieldValue("TOTALAMOUNT", Container),2)
But THIS fails with "System.FormatException: Input string was not in a correct format."
PLEASE PLEASE PLEASE, does anyone know what I am doing wrong?