I have a list of customers that can be sorted by anywhere from 1 to 6 fields based on a user's selection. The sort fields can be in any order. If I know the fields and the sequence ahead of time, sorting is easy:
customers = customers
.OrderBy(c => c.LastName)
.ThenBy(c => c.City)
.ThenBy(c => c.Age).ToList();
How would I pass in the sort fields at runtime? Is there a way to do something like this?
string sortField1 = "State";
string sortField2 = "City";
string sortField3 = "Type";
customers = customers
.OrderBy(c => c.sortField1)
.ThenBy(c => c.sortField2)
.ThenBy(c => c.sortField3).ToList();
I solved this by chaining .OrderBy statements in a ForEach loop. An .OrderBy gets appended to my Linq query for each sort criterion selected by the user. By wrapping my list in an IQueryable, I'm able to see the Linq query as it is built.
Resulting query:
Have a look at http://tomasp.net/articles/dynamic-linq-queries.aspx for a tutorial on how to build Dynamic LinQ queries at runtime. This should be what you are looking for.