How to handle DBNull DataType for Ms access ??

Hi,

I have problem in using this function to check if the field is empty or null :

Let say , I have connect to a Database and set up Dataset :

Dim Ds as dataset

Dim StrAddr as string

If IsDBNull( DS.tables("tblName").rows(0).item("Address")) then

LbMsg.text =" No address entered."

else

StrAddr = DS.tables("tblName").rows(0).item("Address"))

end if

I have error msg : Can not cast DBNull to string.

All I wanted is to check the field address to see if it is empty or no data entered.

Please help.

How to check ? How to handle if the field has nothing in it at all. How to use IsDBNull() ?

Thanks in advance.

Try this:

StrAddr = DS.tables("tblName").rows(0).item("Address").ToString

If StrAddr ="" then StrAddr = "No Address Entered"

Tim

How to handle boolean values from Access

I use a DataReader to retrieve my database (field)information. Everything works fine when working with strings.

Ex.

string data1 = MyReader["FieldName"].ToString();

But now I want to store a boolean value from the database in a variable, but how? Seems stupid, but I cant get it working. It's an Acces database with a yes/no field in the table. I want something like this:

bool data2 = MyReader["FieldName"];

but then asp.net tells me: cant convert object to bool.

What to do...

Hi,

you need to cast it to boolean

bool data2 = (bool)MyReader["FieldName"];

ok, thanks for your (simple) solution! But I do think this is the ugly way. Isn't there a function like ToString() but then for booleans? Or thould I forget the ugly thing about it and simply use a cast?

You'll see lots of casting when working with .NET so get used to it. :-)

You can useConvert.ToBoolean in .NET (Convert is a helper class in the Framework) if it's the prettier way for you