Question

I’ve a source data which contains the data in month as below:

Oct 2011
Nov 2011
Dec 2011
Jan 2012
Feb 2012

I need to select all the months that invoice falls on to. The invoice has properties below:

Invoice.StartDate=13-10-2011;
Invoice.EndDate=11-01-2012;


sourceData.Where(x => x.SourceDate.Month >= Invoice.StartDate.Month && 
                 x.SourceDate.Year==Invoice.StartDate.Year && 
                 x.SourceDate.Month <= Invoice.EndDate.Month &&
                 x.SourceDate.Year == Invoice.EndDate.Year).ToList();

The above query returns 0. I’m expecting the filtered data source result below:

Oct 2011
Nov 2011
Dec 2011
Jan 2012

Could someone help me to achieve above?

Answer 1

This solution simply creates DateTimes with Day set to 0 so they can be compared directly. It uses query syntax because it’s more convenient for creating the new DateTimes.

startYearMonth = new DateTime(Invoice.StartDate.Year, Invoice.StartDate.Month, 0);
endYearMonth = new DateTime(Invoice.EndDate.Year, Invoice.EndDate.Month, 0);

(from data in sourceData
 let dataYearMonth = new DateTime(data.SourceDate.Year, data.SourceDate.Month, 0)
 where dataYearMonth >= startYearMonth && dataYearMonth <= endYearMonth
 select data).ToList();