Question

Ive got ths really annoying issue I have grouped a set of data and I cant get to the data within the group. I can get to the key bit not the data..

I have a load of data that is in the form

Data.Period = x
Data.Adjustment = y

I perform a GroupBy

var groupedData = Data.GroupBy(x => x.Period new {x.Period});

This brings back (according to linq) my hierarchical data which is starting to look how I want it. Id like to iterate through the contents but cant…How do I do this? and how do I…

Work how to get to the Data.Adjustment without using a projection. And I dont want to project yet because I have to perform another grouping….help! 🙂

Answer 1

The IGrouping<TKey, TElement> interface inherits IEnumerable<TElement>:

foreach (var group in groupedData)
{
    var groupKey = group.Key;
    foreach (var groupedItem in group)
        DoSomethingWith(groupKey, groupedItem);
}

I note that you will be better off using this for your query, however:

var groupedData = Data.GroupBy(x => x.Period); 

rather than this:

var groupedData = Data.GroupBy(x => new {x.Period}); 

If, for example, you wanted to average the adjustments, you could do this:

foreach (var group in groupedData)
    Console.WriteLine("Period: {0}; average adjustment: {1}", group.Key, group.Average(i => i.Adjustment));