Nested group by in LINQ in a query

P K

5y1.9kVisual Basic .NET

Please suggest any way to use nested group by in LINQ in a query

3 Replies

Know the answer? Post it — somebody with the same question will find it here.

P K5y ago
dataProps = (from childProperty in _context.SubCatPropsChildProperties.Where(c => c.PropertyId == property.Id && c.IsActive == true && c.IsDeleted == false)
select new
{

PropertyName = childProperty.PropertyName,
PropertyTitle = childProperty.PropertyTitle,
PropertyType = childProperty.PropertyType,
PropertyDescription = childProperty.PropertyDescription,
PropertyValue = childProperty.PropertyValue,
MinLength = childProperty.MinLength,
MaxLength = childProperty.MaxLength,

SubChildProperties = (from subChildProperty in _context.ChildPropsProperties.Where(c => c.PropertyId == childProperty.PropertyId && c.IsActive == true && c.IsDeleted == false)
select new
{
PropertyName = subChildProperty.PropertyName,
PropertyTitle = subChildProperty.PropertyTitle,
PropertyType = subChildProperty.PropertyType,
PropertyDescription = subChildProperty.PropertyDescription,
PropertyValue = subChildProperty.PropertyValue,

}).AsEnumerable()
}).AsEnumerable()

Please suggest dataProps and SubChildProperties by grouping, inside SubChildProperties there also need grouping
Mageshwaran R5y ago
1. var query = from bug in RawListData
2. group bug by new bug.Category into grouped
3. select new {
4. Category = grouped.Category,
5. Counts = from bug in grouped
6. group bug by grouped.Priority into g2
7. select new { Priority = g2.Key, Count = g2.Count() }
8. };
10. foreach (var result in query)
11. {
12. Console.WriteLine("{0}: ", result.Category);
13. foreach (var subresult in result.Counts)
14. {
15. Console.WriteLine(" {0}: {1}", subresult.Priority, subresult.Count);
16. }
17. }

Rajanikant Hawaldar5y ago

refer below blog.

https://www.c-sharpcorner.com/blogs/nested-group-in-linq1

following example shows how to create nested groups in a LINQ query expression.

public void QueryNestedGroups()
{
var queryNestedGroups =
from student in students
group student by student.Year into newGroup1
from newGroup2 in
(from student in newGroup1
group student by student.LastName)
group newGroup2 by newGroup1.Key;
// Three nested foreach loops are required to iterate
// over all elements of a grouped group. Hover the mouse
// cursor over the iteration variables to see their actual type.
foreach (var outerGroup in queryNestedGroups)
{
Console.WriteLine($"DataClass.Student Level = {outerGroup.Key}");
foreach (var innerGroup in outerGroup)
{
Console.WriteLine($"\tNames that begin with: {innerGroup.Key}");
foreach (var innerGroupElement in innerGroup)
{
Console.WriteLine($"\t\t{innerGroupElement.LastName} {innerGroupElement.FirstName}");
}
}
}
}
/*
Output:
DataClass.Student Level = SecondYear
Names that begin with: Adams
Adams Terry
Names that begin with: Garcia
Garcia Hugo
Names that begin with: Omelchenko
Omelchenko Svetlana
DataClass.Student Level = ThirdYear
Names that begin with: Fakhouri
Fakhouri Fadi
Names that begin with: Garcia
Garcia Debra
Names that begin with: Tucker
Tucker Lance
DataClass.Student Level = FirstYear
Names that begin with: Feng
Feng Hanying
Names that begin with: Mortensen
Mortensen Sven
Names that begin with: Tucker
Tucker Michael
DataClass.Student Level = FourthYear
Names that begin with: Garcia
Garcia Cesar
Names that begin with: O'Donnell
O'Donnell Claire
Names that begin with: Zabokritski
Zabokritski Eugene
*/