I have a LINQ query which returns IEnumerable<List<int>> but i want to return only List<int> so i want to merge all my record in my IEnumerable<List<int>> to only one array.
Example :
IEnumerable<List<int>> iList = from number in
(from no in Method() select no) select number;
I want to take all my result IEnumerable<List<int>> to only one List<int>
Hence, from source arrays:
[1,2,3,4] and [5,6,7]
I want only one array
[1,2,3,4,5,6,7]
Thanks
Try SelectMany()
var result = iList.SelectMany( i => i );
SelectMany( i => i ) ? I've seen this syntax used a lot but it seems a degenerate use of the select feature, so I would have expected the language designers to come up with a shortcut syntax specifically for lists of lists
IEnumerable ourselves!With query syntax:
var values =
from inner in outer
from value in inner
select value;
iList.SelectMany(x => x).ToArray()
.ToArray()? -- That's kind of circumstantial -- if you only need to iterate once -- or if the items are likely to change, then .ToArray() is definitely not what you want. But with static items that you're going to enumerate multiple times, .ToList() or .ToArray() will give a performance improvement (at the cost of slightly higher memory usage, which, is usually a pretty good deal).
List<int>, so .ToList() would then be the correct choice.
If you have a List<List<int>> k you can do
List<int> flatList= k.SelectMany( v => v).ToList();
Like this?
var iList = Method().SelectMany(n => n);
