Question

In LINQ, is it possible to have conditional orderby sort order (ascending vs. descending).

Something like this (not valid code):

bool flag;

(from w in widgets
 where w.Name.Contains("xyz")
 orderby w.Id (flag ? ascending : descending)
 select w)

Answer 1

If you build the expression incrementally you can do this. Generally easier using expressions rather than comprehension expressions:

var x = widgets.Where(w => w.Name.Contains("xyz"));
if (flag) {
  x = x.OrderBy(w => w.property);
} else {
  x = x.OrderByDescending(w => w.property);
}

(Assuming the Widget’s property is basis of sort since you don’t list one.)