Question

I have a list of Fees (linq to sql entity- if relevant) – Upper Fee, Lower Fee (both are decimal values). I am passing in a property value – say 90000 and I want to check if this property value best matches one (or first value out of many) from the list of fees.

The fees could be something like…

(lower fee – upper fee)

0 - 50000
50001 - 75000
75001 - 90000
90001 - 140000
190000 - 500000

Out of these values, 90000 is best matched for something like 75001 – 90000 band, so I want to pull out that FeeDetail entity. I dont really know what operator to use, any help is appreciated, my code so far is…

    [Test]
    public void GetFeeRange()
   {
        const int id = 44;
        var propValue = 90000;

        //get a specific fee entity, then get the range of fee details...
        var recommendedFees = RepoSession.All<Fee>()
            .Where(x =>
                   x.ClientSurveyTypeID == id)
            .GroupJoin(_readOnlySession.All<FeeDetail>(),
                       x => x.FeeID,
                       y => y.FeeID,
                       (x, y) => new
                                     {
                                         FeeDetail = y.DefaultIfEmpty()
                                     })
            .Select(x => x.FeeDetail)
            .SingleOrDefault();

        Assert.IsNotNull(recommendedFees);

       //order fees by lowest fee - *the bit I am stuck on*
        var bestMatch = recommendedFees.OrderBy(x => x.Lower)
            .TakeWhile(x => propValue >= x.Lower || propValue <= x.Upper)
            .FirstOrDefault();



    }

Question- how would I perform the range checks? What operator of linq do I need? Not sure if I should perform a takewhile then, get the best fee from that range?

NOTE: the fees could very easily be…

(lower fee – upper fee)

0 - 50000
50001 - 75000
95001 - 140000
190000 - 500000

If a best match is found, pull that out OR get the closest match… maybe I can show a list of available matches if one is not (near enough) an exact match

Answer 1

Just a simple .Where should be fine:

var bestMatch = recommendedFees
              .Where(x => propValue >= x.Lower && propValue <= x.Upper)
              .OrderBy(x => x.Lower)                  
              .FirstOrDefault();