Question

I’ve lately been migrating from Delphi to C#. I find C sharp very powerful and the IDE is awesome. There are some unaccustomed stuff though.

On the database side I have two inner-related tables. Students and Categories. I keep CategoryID in the students table as foreign key. I want to link a DataGridView to the Students table.

When I add a new student I want to be ale to also choose the student’s Category from the dropdown list that list of available Categories. In Delphi we have an opportunity to add a lookup column to table so that it keeps CategoryID in the backgound but displays CategoryName.

How do I do it in C#? Is it possible through DataRelation? If yes, how?

Answer 1

… You don’t mention data technology (Linq etc.) or interface (e.g. Winforms, Webforms etc,) so it is far too hard to help you….

But I have done something similar and I would treat it as two queries, first do a select category.name to populate the drop down box, then something along the lines of

int _temp = select category.id where category.name == dropdownbox.selectedtext

then in your insert command for the student, you simply provide the int _temp.