Initialize an array of int with a range of numbers

Question

I want to initialize an array of int and populate it with a range of numbers:

return new int[].Populate(30,50);

So then I would have an array with 30, 31, 32, 33... - 50

The question shouldn't be closed. Initializing an array is not the same as creating a sequence. — Daniil Palii, May 10 '22 at 15:32

score 78 · Accepted Answer · answered Mar 27 '12 at 23:03

78

You can use Enumerable.Range() to e.g. return an array of 21 integers starting at 30:

return Enumerable.Range(30, 21).ToArray();

answered Mar 27 '12 at 23:03

BrokenGlass

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You need to extend the count to 21 (it includes the starting number). – Justin Niessner Mar 27 '12 at 23:05
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Fixed - considered OPs problem more of an example – BrokenGlass Mar 27 '12 at 23:05

score 25 · Answer 2 · answered Mar 27 '12 at 23:03

25

Use Enumerable.Range

var array = Enumerable.Range(30, 21).ToArray();

This will result in a sequence of 21 values starting at 30. Simply put, you get your { 30 ... 50 } array.

answered Mar 27 '12 at 23:03

Anthony Pegram

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Is this as fast as a for loop? – Sam Mar 27 '12 at 23:08
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@SamStriano possibly; why don't you try it and see. – phoog Mar 27 '12 at 23:10
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@phoog If somebody already knows the answer, it will save him some time to set up a project to test it – Denny Sep 19 '16 at 18:34

score 11 · Answer 3 · answered Nov 07 '16 at 08:46

Using a for loop is actually faster than using Enumerable.Range().ToArray()

I measured it for creating an array of 1 000 000 elements.

int[] array = Enumerable.Range(0, 1000000).ToArray(); takes 9ms, while creating an array int[] array2 = new int[1000000]; and filling it in a for loop took only 3ms.

Initialize an array of int with a range of numbers

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