OrderBy search results that startswith searcch word then by results that contains search word-CodePudding

I have an object like this:

  public class MyObject
{
    public List<string> Names { get; set; }
    // other props
}

and I have a filtered List like this :

   var freeText = "comm";
    var list = new List<MyObject>(); // Initialized

    var searchResult = list.Where(o =>
        o.Names.Any(n => n.ToLower().StartsWith(freeText.ToLower())) ||
        o.Names.Any(n => n.ToLower().Contains(freeText.ToLower())));

and it's working fine but, what I'm trying to do is to get the search results ordered by starts with first then by contains.

ex:

Obj 1 {Names : [ "free communication" ,"some name"]},
Obj 2 { Names : ["communcation Center", "whatever"]}

I want the result to be [Obj2, Obj1].

I tried to orderBy index of freeText but it doesn't seem to work on an array/list of string. I tried to ulter the solution at This question so it works on array instead of string but it didn't work. any idea how to to this?

CodePudding user response：

You can implement a simple scoring mechanism where you'll capture two flags (startsWith and contains) and use those flags both for filtering and for sorting:

var result = list.Select(item => new
{
    item,
    startsWith = item.Names.Any(n => n.ToLower().StartsWith(freeText.ToLower())),
    contains = item.Names.Any(n => n.ToLower().Contains(freeText.ToLower())),
})
.Where(item => item.startsWith || item.contains)
.OrderByDescending(item => item.startsWith)
.ThenByDescending(item => item.contains)
.Select(x => x.item);