Exercise: Shopping days till Xmas using skip/anonymous types

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Category ==> Visual C Sharp  (65 exercises)
Topic ==> Advanced LINQ  (3 exercises)
Level ==> Harder than average
Course ==> Adv C# | Classes & LINQ
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It's the first of November 2020, and you haven't done ANY Christmas shopping.  Also:

  • you can only bear to shop on a Monday;
  • you know you're doing something next Monday; and
  • you can't bear to shop on the last 2 Mondays before Christmas.

To start, add the items in the above folder into your project, and make the frmShoppingDays form the default form.  When you click on the button, it should update the form caption:

Shopping days form

When you click on the button, you should see that there are 54 shopping days till Christmas in the form's caption, as here.


Now write a query expression which returns an anonymous type with two properties:

  • PossibleDate - a Monday between "now" and Christmas
  • CountdownDays - the number of days between this date and Christmas.

Your query expression should sort the dates in reverse order, then skip the first two.  Don't forget only to count Mondays.

Now iterate over this (you'll need to reverse it using the Reverse method, and skip the first item) to get this:

Shopping days left

What you should see when you click on the button now.


There are no doubt easier ways to do this, but none which teaches LINQ so well!

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