Sum distinct

Question

User2054207217 posted

I have a MVC model that I enumerate into a table. Everything works fine. But, I have a month-to-date value that I need to add, but only add the distinct columns in the footer.

Manager	Employee	Date	Today's Sale	MTD Sale
John	Steve	4/1/2020	12	25
John	Steve	4/14/2020	13	25
Will	Joe	4/12/2020	4	10
Will	Joe	4/23/2020	6	10
		Total	35	35 (25+10)

I am able to get the Total for Today's Sale by using Model.Sum(i => i.TodaysSale) and it works fine.

How do I accomplish the Total for MTD sale that gets  sum of distinct values (25+10) ?

Thanks.

Answer 1

User1686398519 posted

Hi progdever,

You can use DistinctBy() to achieve your needs.

1. You need to import Microsoft.Ajax.Utilities.
2. A useful extension method provided by #.NET is Distinct(), but it does not accept the Distinct() overload of Lambda expressions, so you can choose DistinctBy() if you want to use Lambda expressions.

   • @Model.DistinctBy(t => t.MTDSale).Sum(t => t.MTDSale)

More details, you could refer to below code:

Model

    public class Test37
    {
        public string Manager { get; set; }
        public string Employee { get; set; }
        public string Date { get; set; }
        public decimal TodaySale { get; set; }
        public decimal MTDSale { get; set; }
    }

Controller

        public ActionResult Index()
        {
            List<Test37> testlist = new List<Test37>();
            testlist.Add(new Test37 {Manager= "John", Employee= " Steve ", Date= "4/1/ 2020", TodaySale =12,MTDSale=25});
            testlist.Add(new Test37 { Manager = "John", Employee = "Steve", Date = "4/14/ 2020", TodaySale =13, MTDSale =25 });
            testlist.Add(new Test37 { Manager = "Will", Employee = "Joe", Date = "4/12/ 2020", TodaySale = 4, MTDSale =10 });
            testlist.Add(new Test37 { Manager = "Will", Employee = "Joe", Date = "4/23/ 2020", TodaySale = 6, MTDSale = 10 });
            return View(testlist);
        }

View

@model IEnumerable<WebApplication26.Models.Test37>
@using Microsoft.Ajax.Utilities;
<table class="table">
    <tr>
        <td>Manager</td>
        <td>Employee</td>
        <td>Date</td>
        <td>Today's Sale</td>
        <td>MTD Sale</td>
    </tr>
    @foreach (var item in Model)
    {
        <tr>
            <td>@item.Manager</td>
            <td>@item.Employee</td>
            <td>@item.Date</td>
            <td>@item.TodaySale</td>
            <td>@item.MTDSale</td>
        </tr>
    }
    <tr>
        <td></td>
        <td></td>
        <td></td>
        <td>@Model.Sum(t=>t.TodaySale) </td>
        <td>@Model.DistinctBy(t => t.MTDSale).Sum(t => t.MTDSale)</td>
    </tr>
</table>

Here is the result.

Best Regards,

YihuiSun

Answer 2

User2054207217 posted

Hi YihuiSun,

Thanks very much for this example. There is one change I need, instead of distinct on the MTD Sale, how can I do a distinct on the Employee, and then add the MTDSales sum.

I tried:

@Model.DistinctBy(t => t.Manager + t.Employee).Sum(t => t.MTDSale) 
@Model.DistinctBy(t=> new{t.Manager , t.Employee}).Sum(t=>t.MTDSale)

Both are giving me 60 as total. Thanks.

Answer 3

User2054207217 posted

I was able to fix this. Thanks again.