Question

I have a table that contains a nvarchar column that allows nulls.

I have a method in VB.NET that has a optional description variable that is set to Nothing

Public Shared Sub InsertDescription(Optional ByVal Description As String = Nothing)
{
    //Insert Description Procedure Call
}

If I call this method like:

InsertDescription();

It fails saying that the procedure was expecting the @Description, but was not provided. The only way I have found to remedy this is to set the default value to “” or to not make it optional and just pass in “”, but I don’t want to insert an “” string into the database tables description column, I want to pass in null by default.

Answer 1

Try using the DbNull.Value

If a database field has missing data,
you can use the DBNull.Value property
to explicitly assign a DBNull object
value to the field.

—
Doesn’t this work?

if (Description is nothing) then ' Set SP param to dbnull.value

If not, could you post some more relevant code?