MVC 2.0 - JqGrid Sorting with Multiple Tables

Question

I am in the process of implementing the jqGrid and would like to be able to use the sorting functionality. I have run into some issues with sorting columns that are related to the base table.

Here is the script to load the grid:

public JsonResult GetData(GridSettings grid)
{
    try {
        using (IWE dataContext = new IWE())
        {
            var query = dataContext.LKTYPE.Include("VWEPICORCATEGORY").AsQueryable();

            ////sorting
            query = query.OrderBy<LKTYPE>(grid.SortColumn,
                grid.SortOrder);


            //count
            var count = query.Count();

            //paging
            var data = query.Skip((grid.PageIndex - 1) * grid.PageSize).Take(grid.PageSize).ToArray();

            //converting in grid format
            var result = new
            {
                total = (int)Math.Ceiling((double)count / grid.PageSize),
                page = grid.PageIndex,
                records = count,
                rows = (from host in data
                        select new
                        {
                            TYPE_ID = host.TYPE_ID,
                            TYPE = host.TYPE,
                            CR_ACTIVE = host.CR_ACTIVE,
                            description = host.VWEPICORCATEGORY.description
                        }).ToArray()
            };

            return Json(result, JsonRequestBehavior.AllowGet);
        }
    }
    catch (Exception ex)
    {
        //send the error email
        ExceptionPolicy.HandleException(ex, "Exception Policy");
    }

    //have to return something if there is an issue
    return Json("");
}

As you can see the description field is a part of the related table("VWEPICORCATEGORY") and the order by is targeted at LKTYPE. I am trying to figure out how exactly one goes about sorting that particular field or maybe even a better way to implement this grid using multiple tables and it's sorting functionality.

Thanks in advance, Billy

Answer 1

You're sorting the wrong query.

Change your code to:

        var query = from host in dataContext.LKTYPE
                    select new
                    {
                        TYPE_ID = host.TYPE_ID,
                        TYPE = host.TYPE,
                        CR_ACTIVE = host.CR_ACTIVE,
                        description = host.VWEPICORCATEGORY.description
                    };

        ////sorting
        query = query.OrderBy(grid.SortColumn,
            grid.SortOrder);

        //count
        var count = query.Count();

        //paging
        var data = query.Skip((grid.PageIndex - 1) * grid.PageSize).Take(grid.PageSize).ToArray();

        //converting in grid format
        var result = new
        {
            total = (int)Math.Ceiling((double)count / grid.PageSize),
            page = grid.PageIndex,
            records = count,
            rows = data.ToArray()
        };

Note that the Include() is completely unnecessary in your example since you're projecting.

Answer 2

I have a post on my blog that shows how I rolled sorting and paging functionality of jqGrid into a very reusable pattern with MVC.

My post is here: http://www.journeymandeveloper.com/Home/View/4fae1468-3e08-46e0-9208-9e7104d7956b/Server-side%20Paging%20and%20Sorting%20with%20jqGrid

It contains a class that you take in as a parameter on the action method, and it does all the work for you. All you really need to do is give it an IQueryable when you want the results.