Orderby not working

Question

Orderby not working

asp.net-mvc c# dynamic-linq entity-framework linq

Question

I am sorting on multiple criteria using dynamic sorting, here's my code:

    public ActionResult WebGrid(int page = 1, int rowsPerPage = 10, string sortCol = "OrderID", string sortDir = "ASC", string sortSecCol = "OrderID", string sortSecDir = "ASC")
    {
        List<Orders> res;

        using (var nwd = new NorthwindEntities())
        {
            var _res = nwd.Orders
                .AsQueryable()
                .OrderBy(sortCol + " " + sortDir, sortSecCol + " " + sortSecDir)
                .Skip((page - 1) * rowsPerPage)
                .Take(rowsPerPage)
                .Select(o => new Orders  
                {

What I am trying to do in here is I want the column OrderID be the secondary sort whenever it is not a primary sort, but it didn't work when I actually selected other column as a primary sort.

In order words, when other column is select as primary sort in descending order, OrderID should also be in descending order, I am not sure what did I missed in my code.

The OrderBy method I used is come from here (MSDN).

Phantom

Popular Answer

try this:

    if (sortCol == "OrderID" && sortDir == "ASC")
    {
        _res = l.OrderBy(x => x.OrderId).ThenBy(x => x.AnotherField);
    }
    if (sortCol == "OrderID" && sortDir == "DESC")
    {
        _res = l.OrderByDescending(x => x.OrderId).ThenByDescending(x => x.AnotherField);
    }
    if (sortCol == "AnotherField" && sortDir == "ASC")
    {
        _res = l.OrderBy(x => x.AnotherField).ThenBy(x => x.OrderId);
    }
    if (sortCol == "AnotherField" && sortDir == "DESC")
    {
        _res = l.OrderByDescending(x => x.AnotherField).ThenByDescending(x => x.OrderId);
    }

    _res.Skip((page - 1) * rowsPerPage)
            .Take(rowsPerPage)
            .Select(o => new Orders  
            {

burzhuy

View more on Stack Overflow

Ivan Stoev · Accepted Answer · 9/8/2016 10:24:55 PM

The method you are using has the following signature:

public static IQueryable<T> OrderBy<T>(
    this IQueryable<T> source,
    string ordering,
    params object[] values
)

so the sortSecCol + " " + sortSecDir goes to values argument, while the whole ordering is supposed to be provided as comma separated list in the ordering argument.

You can use something like this instead:

var ordering = sortCol + " " + sortDir;
if (sortSecCol != sortCol)
    ordering += ", " + sortSecCol + " " + sortSecDir;
...
   .OrderBy(ordering)
...

Orderby not working

Question

Fastest Entity Framework Extensions

Accepted Answer

Popular Answer

Performance

Expression Evaluator