Vtable.FieldCount problem was: Illegal Cast Exception

[Steve Albin]

On 10/17/09 at 11:08 AM, steve at steve-albin.com (Steve Albin) wrote:

>Unfortunately, my app is a mixed bag of techniques that has 
>changed as I learned more.  I've been working on it since the 
>days of Valentina 1.  I use SQL to create my cursors and then 
>use VCursor classes to access the data.  It's worked fine for 
>me up to now.
>
>I'm using the vTable.FieldCount property when I need to access 
>fields from a SELECT statement that combines two tables.  I 
>generally do this:
>
>cursor.SqlExecute("SELECT tableA.*, tableB.fld1, tableB.fld2")
>
>Then I get the FieldCount of TableA so I can do this:
>
>return cursor.Field(DB.TableA.FieldCount+1).GetString
>
>to get tableB.fld1 without having to worry about changing that 
>code if I ever add fields to TableA.
>
>I've submitted a project and DB to Mantis that demonstrates the 
>problem.  ID = 0004590.


Just for the record, this turned out to be a problem in my code 
and not with Valentina.

In the release notes, there is an item mentioning a fix to a 
VTable constructor issue.  I was not calling the 
Super.constructor in my VTable classes.  In version 4.1, this 
was not necessary.  Evidently, in version 4.3, it is necessary.

Without calling the super, when creating a DB you get a DB with 
no tables.  But, when opening an existing DB, everything works 
except any method calls to the class.  I was only using the 
classes to open the DB and a few other minor things.  All my SQL 
and other API calls were fine.

Sorry for any confusion I may have caused.

Steve

-- 
Steve Albin - Montclair, NJ
http://www.jazzdiscography.com/
http://www.steve-albin.com/