Question

I am playing with the new stuff of C#3.0 and I have this code (mostly taken from MSDN) but I can only get true,false,true… and not the real value :

        int[] numbers = { 5, 4, 1, 3, 9, 8, 6, 7, 2, 0 };          var oddNumbers = numbers.Select(n => n % 2 == 1);          Console.WriteLine('Numbers < 5:');         foreach (var x in oddNumbers)         {             Console.WriteLine(x);         } 

How can I fix that to show the list of integer?

Answer 1

Change your ‘Select’ to a ‘Where’

    int[] numbers = { 5, 4, 1, 3, 9, 8, 6, 7, 2, 0 };      var oddNumbers = numbers.Where(n => n % 2 == 1);      Console.WriteLine('Odd Number:');     foreach (var x in oddNumbers)     {         Console.WriteLine(x);     } 

The ‘Select’ method is creating a new list of the lambda result for each element (true/false). The ‘Where’ method is filtering based on the lambda.

In C#, you could also use this syntax, which you may find clearer:

        var oddNumbers = from n in numbers                          where n % 2 == 1                          select n; 

which the compiler translates to:

var oddNumbers = numbers.Where(n => n % 2 == 1).Select(n => n);