EF/Gridview/Related tables

Grodnik · October 9th, 2015, 04:11 PM

There must be a way to modify the code on P 503 to include GenreName instead of GenreID in the Gridview. Please show me how that might work. Thank you.

Imar · October 10th, 2015, 04:02 AM

Hi there,

There are a couple of different ways to do it. One solution is to use Include (see page 505) to include the Gene and then build a new anonymous object (see page 512) to select the properties from Review you need and also include the Genre.Name, like this:

Code:

var authorizedReviews = from review in myEntities.Reviews.Include("Genre")
                        where review.Authorized == true
                        orderby review.CreateDateTime descending
                        select new
                        {
                          review.Id,
                          review.Title,
                          review.Summary,
                          review.Body,
                          review.GenreId,
                          review.Genre.Name,
                          review.Authorized,
                          review.CreateDateTime,
                          review.UpdateDateTime
                        };

GridView1.DataSource = authorizedReviews;
GridView1.DataBind();

This selects all properties from the Review but also includes review.Genre.Name which is then rendered in the GridView in the Name column. If you want to rename it, you could do something like this:

GenreName = review.Genre.Name,

Instead of relying on automatically created columns you can also convert the GridView to templates and then bind the genre to Genre.Name instead of GenreId.

Hope this helps,

Imar

Grodnik · October 17th, 2015, 02:51 PM

Thank you - very helpful. I just used BoundFields in the Gridview instead of templates. I created an anonymous type that included the tableID of the main table, but I didn't include tableID as a gridview column. Nonetheless, when I clicked on the row command button, the subroutine managed to convert the index to the right tableID. I'm not exactly sure how that works. Have you got a page reference?

Imar · October 22nd, 2015, 05:22 AM

You probably have a DataKeyNames attribute set that ASP.NET uses to keep track of the primary key(s) for each row,

Hope this helps,

Imar