Dynamic Data 3.5 SP1

For just one of my Dynamic Data Entities tables I would like to control the order of the displayed records, specifically I would like to order a date column descending.

The (SQL Server) table is named "EventLog" with a column "datLocalTimestamp" of type DateTime.

In my "meta" .cs file, I have tried adding the following:

[MetadataType(typeof(EventLogMetaData)), DisplayColumn("datLocalTimestamp", "datLocalTimestamp", true)]

public partial class EventLog

{

}

This did nothing.  Next, I tried adding a IComparer class:

internal class EventLogCompare : IComparer<EventLog>

{

    public int Compare( EventLog logA, EventLog logB )

    {

        return DateTime.Compare( logB.datLocalTimestamp, logA.datLocalTimestamp);

    }

}

I put a breakpoint on the Compare method but it is never invoked.

Do I need to modify the Page_Load event in the ListDetails.aspx.cs page template file?  That doesn't seem like the way to go for a single table...

Thanks for your help.

I don't think that the Compare method would ever be called as your are either useing Linq to SQL or Entity Framework so the order by statement would be sent to the DB the thing to do (if you are using SQL Server) would be to run an SQL trace in the background whilst runnung your app.

You'll then see if the order by is sent to the db.

 Whether or not the DisplayColumn attribute is specified, a trace shows that the query has only the primary key in the ORDER BY clause.

This could just be a bug an undocumeted feature I'll have a look with Northwind and get back

I don't belive it has anything to do with initial sort, what it does is set the sort on any dropdown list that refer to this column so if you have an other table that you could filter by this on the you DisplayColumn would affect this not the table. hope that makes sense.

I would create a custom page and add the initial sort to the GridView using the: 

GridView1.Sort("ColumnName, ColumnName", SortDirection.Descending);

Thanks for the input.  Is the best option to copy the existing ListDetails.aspx page to a new name and then update the routes in global.asax to use the new jpage? 

What you do is much easyer than that:

1. Create a folder in the ~/DynamicData/CustomPages/ folder by that plural name of the table i.e. Order would be Orders and Category would be Categories
2. Copy the page you want to customise in the and then edit it to you hearts content it will only be called for the one table

hope that makes sense

Under CustomPages I created a sub-directory named the same as my table (named "EventLog"; the plural form did not work).

I copied the ListDetails.aspx and code file to the new directory.  In the Page_Load event I added the line:

GridView1.Sort("datLocalTimestamp", SortDirection.Descending);

This did the trick.

The other benefit was that this allowed me to disable editing on this table (comment out the "if (_table.IsReadOnly)" statement allowing the contents of the if block to execute).  I could find no way to disable editing via the metadata code file.  Is there any documentation which will help me figure out which technique (routing, custom pages, metadata attributes) to use for various scenarios.  For example, since I can hide columns with the "ScaffoldColumn(false)" attribute, I believe there should be a way to hide the "Edit/Delete/Insert" control column using attributes.  I believe there should be attributes for the table which would configure the initial sort order.

Thanks for all the help.

You could easily implement doing this via meta data your self by adding you own attribute class: 

[AttributeUsage(AttributeTargets.Class, AllowMultiple = false)]
public class DisableEditingAttribute : Attribute
{
    public Boolean Disable { get; set; }

    public DisableEditingAttribute() : this(false) { }

    public DisableEditingAttribute(Boolean disable)
    {
        Disable = disable;
    }
}

// Disable various options if the table is readonly
var editingDisabled = table.Attributes.OfType().DefaultIfEmpty(new DisableEditingAttribute()).FirstOrDefault();
if (table.IsReadOnly || editingDisabled.Disable)
{
    GridView1.Columns[0].Visible = false;
    InsertHyperLink.Visible = false;
}

This would allow you to specify disable editing in metadata: 

[MetadataType(typeof(ProductMD))]
[DisableEditing(true)]
public partial class Product
{
}