应用分组依据，然后全选

Question

I have a list which has following items :

Id
Name
Currency
Fund

I am applying group by on this list as follows :

var testData = from fl in fundsList
                           group fl by new { fl.Name } into groupedData
                           select new
                           {
                               groupedData.Key.Name,
                           };  

But this gives me only Name in the selected data. What I want is apply group by on basis of Name and get all items ie Id, Name, Currency and Fund in select . I tried accessing others in select, but they don't come with Key.

Answer 1

Try this:

var testData = fundsList.GroupBy(fl => fl.Name);

Now you will get an IEnumerable<IGrouping<T>> , which containes many key => valueCollection items.

Answer 2

var testData = from fl in fundsList
                           group fl by new { fl.Name } into groupedData
                           select new
                           {
                              GroupName=  groupedData.Key.Name,
                              Items = grp.ToList()
                           };  

Answer 3

groupedData within your query implements IEnumerable<YourEntity> with items that belongs to that group, so you can easily do following:

var testData = from fl in fundsList
                           group fl by fl.Name into groupedData
                           select new
                           {
                              Name = groupedData.Key.Name,
                              Items = grp.ToList()
                           };  

Or in method based query:

var testData = fundsList.GroupBy(fl => fl.Name)
                        .Select(g => new { Name = g.Key, Items = g.ToList() });

Every item withint testData collection will have two properties:

• Name with group name
• Items with all items that belongs to the group