Detailsview not appearing

Imar · October 8th, 2014, 11:10 AM

Isn't this the same issue as before? The column you are trying to update is not part of your INSERT or UPDATE statement...

Imar

markhh · October 8th, 2014, 03:58 PM

Hi Imar, yes I agree with your post. It looks like I am misunderstanding what the events are capable of or how they work. I thought after reading pages 469 to 472 that the method below by itself was capable of updating the 'Your_Age' column. Can you enlighten me,

Regards
Mark

Code:

 protected void DetailsView1_ItemInserting(object sender, DetailsViewInsertEventArgs e)
    {
        e.Values["Your_Age"] = 22;
    }

Imar · October 8th, 2014, 04:39 PM

The DetailsView and associated SqlDataSource control can get data from the database, but also send updates back. For the updates, you can use INSERT, UPDATE and DELETE commands.

All the SqlDataSource knows about the table is what you specify in the respective commands. This means it cannot update columns you don't specify in the SQL command.

In order to build up the values for the command, the control looks at the various *Parameters you specify in the code. Each parameter maps to a placeholder in the SQL statement. When you build your query using the query designer, VS generates the appropriate placeholders and parameters for you.

When the data is sent to the database, the DetailsView provides the data the user entered in the various web controls. The SqlDataSource then uses that data to build up the SQL statement. Using the various events you can *change* the value of the various parameters. E.g. this:

e.Values["Your_Age"] = 22;

overrides whatever the Your_Age parameter had as a value *provided you specified it as a parameter in the SqlDataSource control*.

Does this help?

Imar

markhh · October 24th, 2014, 02:04 PM

Hi Imar, yes very helpful and many thanks for all your replies with this one,

Best Wishes
Mark