Convert IEnumerable<IGrouping<,>> to array

Question

Is there an easy way of converting remaining in the following code to a 1-D array.

var groups = data.OrderBy(d => d.Time).GroupBy(d => d.Period);
var first = groups.First().ToArray();
var remaining = groups.Skip(1).??

Answer 1

var remaining = groups.Skip(1).SelectMany(g=>g).ToArray();

Answer 2

使用SelectMany可以“展平”集合的集合：

var remaining = groups.Skip(1).SelectMany(d => d).ToArray();