MvcContrib Grid Sorting on complex object

Question

I am trying to work with MvcContrib Grid control. But I cannot seem to get the sorting to work on complex objects that hold other objects.

I have setup my controller/classes/Views similar to the OP in this question. Sorting with MVCContrib

I have tried to use the SortColumnName to my childobject.property but it gives me an error saying My main object does not have this property. This is my code snippet

//POCO class

class Issue {
   public int ID {get; get; }
   .....
   public int priorityId {get; set;}
   public virtual Priority priority {get; set;}
}

//Controller code

    public ViewResult Index(int? pageNo, GridSortOptions sort)
    {
        var issues = db.issues.Include(i => i.priority);
        ViewBag.sort = sort; 

        if (!string.IsNullOrEmpty(sort.Column))
        {
            issues = issues.OrderBy(sort.Column, sort.Direction);
        }
        return View(issues.ToList().AsPagination(pageNo ?? 1, 10));
    }

//View code for the Grid

@Html.Grid(Model).Sort(ViewBag.sort as GridSortOptions).Columns(column => {
    column.For(issue => Html.ActionLink(" ", "Edit", new { id = issue.ID, areas = "Issues", controller = "Main"}, new { @id="editBtn"})).Named("Edit");
    column.For(issue => Html.ActionLink(issue.ID.ToString(), "Edit", new {id = issue.ID, areas = "Issues", controller = "Main"})).Named("ID").Sortable(true);
     column.For(issue => issue.priority.codeDesc).Named("Priority").SortColumnName("priority.codeDesc").Sortable(true);
}).Empty("No data found")

When I try to sort on the priority string, it gives me an error saying 'priority.codeDesc is not a property of Issue'.

TIA

Answer 1

The issue here isn't actually related to the grid, but rather to the .OrderBy extension method provided as part of the MvcContrib sorting extensions. This extension is fairly simplistic and I only wrote it to cover simple cases where you want to sort on a direct property of the object, however in your case you're trying to order on a nested property ("priority.codeDesc") which isn't supported - you can't use dot notation with this extension.

You'd either need to switch to using a different mechanism to perform the actual sorting, or if this is a one-off situation then you could hard-code the sorting logic for this particular column (not ideal, but if it's a one off then it's simpler than writing a new sorting mechanism), eg:

if (!string.IsNullOrEmpty(sort.Column))
{
    if(sort.Column == "priority.codeDesc") 
    {
        issues = issues.OrderBy(x => x.priority.codeDesc);
    } 
    else
    {
        issues = issues.OrderBy(sort.Column, sort.Direction);
    }
}