Is there an “upto” method in C#?

Question

Here\'s a bit of code which prints out the squares of the numbers from 0 to 9:

for (int i = 0; i < 10; i++)
    Console.WriteLine(i*i);

Doin

Answer 1

Try Enumerable.Range, possibly in combination with Take or TakeWhile:

IEnumerable values = Enumerable.Range(0, 20)
    .Take(10); // Not necessary in this example

foreach(var value in values)
{
    Console.WriteLine(value);
}

// or ...

foreach(var i in Enumerable.Range(0, 10))
{
    Console.WriteLine(i * i);
}

There is a ForEach on List that you could use to get closer syntax to what you want, but I consider it bad form. It takes a pure query/filter/transform syntax, that works in an effectively immutable fashion, and introduces side-effects.

For your future amusement you might want to check out extension methods, IEnumerable, and yield return. A lot of generator-type functionality and interesting syntax becomes possible when you use those three things in combination. Although I would argue that this particular example isn't the best place to use them because the resulting syntax becomes a mess.