Concatenate an IEnumerable of IEnumerables?

Question

Suppose I have a linq expression that returns a sequence of IEnumerables. How do I concatenate them into a single flat IEnumerable? Concat seems to be limited to combining only two at a time.

Answer 1

What you're looking for is the SelectMany operator that will flatten an IEnumerable> in a single IEnumerable containing all T without materializing the results

IEnumerable<IEnumerable<string>> MyCollection = getdata();
IEnumerable<string> FlatenedData = MyCollection.SelectMany(item=>item);