There is no argument given that corresponds to the required formal parameter - .NET Error

Question

I have been re-factoring one of my old MSSQL Connection helper library and I got the following error:

Severity Code Description Project File Li

Answer 1

I received this same error in the following Linq statement regarding DailyReport. The problem was that DailyReport had no default constructor. Apparently, it instantiates the object before populating the properties.

var sums = reports
    .GroupBy(r => r.CountryRegion)
    .Select(cr => new DailyReport
    {
        CountryRegion = cr.Key,
        ProvinceState = "All",
        RecordDate = cr.First().RecordDate,
        Confirmed = cr.Sum(c => c.Confirmed),
        Recovered = cr.Sum(c => c.Recovered),
        Deaths = cr.Sum(c => c.Deaths)
    });