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892Single-dimensional arrays
893Rectangular arrays
894Jagged arrays
895Array.Copy
896Array.Resize
897Array.Clear
898Array.Sort
899Array.BinarySearch
900Array.FindAll
901Array.ConvertAll
902ArraySegment<T>
903IEnumerable<T> contract
904IEnumerator<T> disposal
905ICollection<T>
906IList<T>
907IReadOnlyCollection<T>
908IReadOnlyList<T>
909ISet<T>
910IReadOnlySet<T>
911Non-generic ICollection
912StructuralComparisons
913Collection expression allocation
914Custom enumerator structs
915Fail-fast enumeration
916List<T>.Capacity
917List<T>.EnsureCapacity
918List<T>.Add
919List<T>.AddRange
920List<T>.Insert
921List<T>.InsertRange
922List<T>.Remove
923List<T>.RemoveAll
924List<T>.RemoveAt
925List<T>.RemoveRange
926List<T>.Find
927List<T>.FindIndex
928List<T>.FindLast
929List<T>.GetRange
930List<T>.Sort
931List<T>.BinarySearch
932List<T>.Reverse
933List<T>.ConvertAll
934List<T>.TrueForAll
935List<T>.ForEach
936List<T>.AsReadOnly
937List<T>.TrimExcess
938List<T>.ToArray
939List<T> enumeration invalidation
940Dictionary hash buckets
941Dictionary.Add vs indexer
942Dictionary.TryAdd
943Dictionary.TryGetValue
944Dictionary.Remove with out value
945Dictionary.EnsureCapacity
946Dictionary.TrimExcess
947Dictionary.Comparer
948Dictionary.Keys and Values
949Dictionary collision handling
950Custom IEqualityComparer<T>
951HashCode.Combine
952StringComparer variants
953HashSet.Add
954HashSet.Contains
955HashSet.UnionWith
956HashSet.IntersectWith
957HashSet.ExceptWith
958HashSet.SymmetricExceptWith
959HashSet.IsSubsetOf
960HashSet.IsProperSupersetOf
961HashSet.Overlaps
962HashSet.SetEquals
963HashSet.TryGetValue
964Mutable dictionary key hazards
965SortedDictionary red-black tree
966SortedDictionary comparer
967SortedDictionary range enumeration
968SortedList array storage
969SortedList capacity tradeoffs
970SortedSet.GetViewBetween
971SortedSet.Min and Max
972SortedSet.Reverse
973LinkedList.AddFirst
974LinkedList.AddLast
975LinkedList.AddBefore
976LinkedList.AddAfter
977LinkedListNode ownership
978LinkedList.Remove node
979Queue.Enqueue
980Queue.Dequeue
981Queue.TryDequeue
982Queue.TryPeek
983Stack.Push
984Stack.Pop
985Stack.TryPop
986Stack.TryPeek
987PriorityQueue.Enqueue
988PriorityQueue.Dequeue
989PriorityQueue.EnqueueDequeue
990PriorityQueue.DequeueEnqueue
991PriorityQueue.UnorderedItems
992PriorityQueue priority comparers
993BitArray bit operations
994OrderedDictionary insertion order
995ReadOnlyDictionary wrappers
996ReadOnlyCollection wrappers
997ObservableCollection change events
998NotifyCollectionChanged actions
999ImmutableArray.Create
1000ImmutableArray.Builder
1001ImmutableArray default vs empty
1002ImmutableArray.AsSpan
1003ImmutableList structural sharing
1004ImmutableList.Builder
1005ImmutableDictionary.SetItem
1006ImmutableDictionary.WithComparers
1007ImmutableHashSet operations
1008ImmutableSortedDictionary
1009ImmutableSortedSet
1010ImmutableQueue
1011ImmutableStack
1012ImmutableInterlocked.Update
1013ImmutableInterlocked.AddOrUpdate
1014FrozenDictionary construction
1015FrozenDictionary lookup
1016FrozenDictionary comparer selection
1017FrozenSet construction
1018FrozenSet vs HashSet performance
1019Frozen collection startup costs
1020Immutable snapshots for configuration
1021Immutable collections JSON support
1022ConcurrentDictionary.GetOrAdd
1023ConcurrentDictionary.AddOrUpdate
1024ConcurrentDictionary.TryUpdate
1025ConcurrentDictionary delegate races
1026ConcurrentDictionary enumeration
1027ConcurrentQueue
1028ConcurrentStack
1029ConcurrentBag thread locality
1030BlockingCollection bounded capacity
1031BlockingCollection.CompleteAdding
1032BlockingCollection.GetConsumingEnumerable
1033Channel.CreateBounded
1034Channel.CreateUnbounded
1035Channel bounded full modes
1036ChannelWriter.WriteAsync
1037ChannelWriter.TryWrite
1038ChannelWriter.Complete
1039ChannelReader.ReadAsync
1040ChannelReader.ReadAllAsync
1041ChannelReader.WaitToReadAsync
1042Channel cancellation
1043Channel completion errors
1044SingleReader and SingleWriter options
1045Channel backpressure design
1046Enumerable.Where predicate
1047Enumerable.Where indexed overload
1048Enumerable.Select projection
1049Enumerable.Select indexed overload
1050Enumerable.SelectMany flattening
1051SelectMany result selector
1052Enumerable.OfType
1053Enumerable.Cast
1054Query let clauses
1055Query multiple from clauses
1056Query continuation into
1057Deferred execution and side effects
1058Streaming vs buffering operators
1059Iterator fusion in LINQ
1060LINQ on arrays vs lists
1061IEnumerable vs IQueryable semantics
1062Custom iterator operators
1063Materialization boundaries
1064Multiple enumeration detection
1065TryGetNonEnumeratedCount
1066Enumerable.Order
1067Enumerable.OrderDescending
1068Enumerable.OrderBy
1069Enumerable.OrderByDescending
1070Enumerable.ThenBy
1071Enumerable.ThenByDescending
1072Stable ordering guarantees
1073Enumerable.Reverse
1074Enumerable.GroupBy key selector
1075GroupBy element selector
1076GroupBy result selector
1077GroupBy equality comparer
1078Enumerable.ToLookup
1079ILookup indexing
1080Enumerable.Join
1081Enumerable.GroupJoin
1082Left outer join with DefaultIfEmpty
1083Composite join keys
1084Enumerable.Zip two sequences
1085Enumerable.Zip three sequences
1086Enumerable.Chunk
1087Adjacent grouping custom operator
1088Enumerable.Distinct
1089Enumerable.DistinctBy
1090Enumerable.Union
1091Enumerable.UnionBy
1092Enumerable.Intersect
1093Enumerable.IntersectBy
1094Enumerable.Except
1095Enumerable.ExceptBy
1096Enumerable.Concat
1097Enumerable.Append
1098Enumerable.Prepend
1099Enumerable.Skip
1100Enumerable.Take
1101Enumerable.SkipWhile
1102Enumerable.TakeWhile
1103Enumerable.SkipLast
1104Enumerable.TakeLast
1105Enumerable.Take with Range
1106Enumerable.DefaultIfEmpty
1107Enumerable.Empty
1108Enumerable.Range
1109Enumerable.Repeat
1110Set operators with custom comparers
1111Enumerable.Any
1112Enumerable.All
1113Enumerable.Contains
1114Enumerable.SequenceEqual
1115Enumerable.First
1116Enumerable.FirstOrDefault explicit default
1117Enumerable.Last
1118Enumerable.LastOrDefault
1119Enumerable.Single
1120Enumerable.SingleOrDefault
1121Enumerable.ElementAt
1122Enumerable.ElementAtOrDefault
1123Enumerable.Count
1124Enumerable.LongCount
1125Enumerable.Sum
1126Enumerable.Average
1127Enumerable.Min
1128Enumerable.Max
1129Enumerable.MinBy
1130Enumerable.MaxBy
1131Enumerable.Aggregate seed
1132Aggregate result selector
1133Enumerable.ToList
1134Enumerable.ToArray
1135Enumerable.ToDictionary
1136Enumerable.ToHashSet
1137Numeric overflow in Sum
1138Empty sequence aggregation behavior
1139Queryable expression translation boundaries

892Single-dimensional arrays
893Rectangular arrays
894Jagged arrays
895Array.Copy
896Array.Resize
897Array.Clear
898Array.Sort
899Array.BinarySearch
900Array.FindAll
901Array.ConvertAll
902ArraySegment<T>
903IEnumerable<T> contract
904IEnumerator<T> disposal
905ICollection<T>
906IList<T>
907IReadOnlyCollection<T>
908IReadOnlyList<T>
909ISet<T>
910IReadOnlySet<T>
911Non-generic ICollection
912StructuralComparisons
913Collection expression allocation
914Custom enumerator structs
915Fail-fast enumeration
916List<T>.Capacity
917List<T>.EnsureCapacity
918List<T>.Add
919List<T>.AddRange
920List<T>.Insert
921List<T>.InsertRange
922List<T>.Remove
923List<T>.RemoveAll
924List<T>.RemoveAt
925List<T>.RemoveRange
926List<T>.Find
927List<T>.FindIndex
928List<T>.FindLast
929List<T>.GetRange
930List<T>.Sort
931List<T>.BinarySearch
932List<T>.Reverse
933List<T>.ConvertAll
934List<T>.TrueForAll
935List<T>.ForEach
936List<T>.AsReadOnly
937List<T>.TrimExcess
938List<T>.ToArray
939List<T> enumeration invalidation
940Dictionary hash buckets
941Dictionary.Add vs indexer
942Dictionary.TryAdd
943Dictionary.TryGetValue
944Dictionary.Remove with out value
945Dictionary.EnsureCapacity
946Dictionary.TrimExcess
947Dictionary.Comparer
948Dictionary.Keys and Values
949Dictionary collision handling
950Custom IEqualityComparer<T>
951HashCode.Combine
952StringComparer variants
953HashSet.Add
954HashSet.Contains
955HashSet.UnionWith
956HashSet.IntersectWith
957HashSet.ExceptWith
958HashSet.SymmetricExceptWith
959HashSet.IsSubsetOf
960HashSet.IsProperSupersetOf
961HashSet.Overlaps
962HashSet.SetEquals
963HashSet.TryGetValue
964Mutable dictionary key hazards
965SortedDictionary red-black tree
966SortedDictionary comparer
967SortedDictionary range enumeration
968SortedList array storage
969SortedList capacity tradeoffs
970SortedSet.GetViewBetween
971SortedSet.Min and Max
972SortedSet.Reverse
973LinkedList.AddFirst
974LinkedList.AddLast
975LinkedList.AddBefore
976LinkedList.AddAfter
977LinkedListNode ownership
978LinkedList.Remove node
979Queue.Enqueue
980Queue.Dequeue
981Queue.TryDequeue
982Queue.TryPeek
983Stack.Push
984Stack.Pop
985Stack.TryPop
986Stack.TryPeek
987PriorityQueue.Enqueue
988PriorityQueue.Dequeue
989PriorityQueue.EnqueueDequeue
990PriorityQueue.DequeueEnqueue
991PriorityQueue.UnorderedItems
992PriorityQueue priority comparers
993BitArray bit operations
994OrderedDictionary insertion order
995ReadOnlyDictionary wrappers
996ReadOnlyCollection wrappers
997ObservableCollection change events
998NotifyCollectionChanged actions
999ImmutableArray.Create
1000ImmutableArray.Builder
1001ImmutableArray default vs empty
1002ImmutableArray.AsSpan
1003ImmutableList structural sharing
1004ImmutableList.Builder
1005ImmutableDictionary.SetItem
1006ImmutableDictionary.WithComparers
1007ImmutableHashSet operations
1008ImmutableSortedDictionary
1009ImmutableSortedSet
1010ImmutableQueue
1011ImmutableStack
1012ImmutableInterlocked.Update
1013ImmutableInterlocked.AddOrUpdate
1014FrozenDictionary construction
1015FrozenDictionary lookup
1016FrozenDictionary comparer selection
1017FrozenSet construction
1018FrozenSet vs HashSet performance
1019Frozen collection startup costs
1020Immutable snapshots for configuration
1021Immutable collections JSON support
1022ConcurrentDictionary.GetOrAdd
1023ConcurrentDictionary.AddOrUpdate
1024ConcurrentDictionary.TryUpdate
1025ConcurrentDictionary delegate races
1026ConcurrentDictionary enumeration
1027ConcurrentQueue
1028ConcurrentStack
1029ConcurrentBag thread locality
1030BlockingCollection bounded capacity
1031BlockingCollection.CompleteAdding
1032BlockingCollection.GetConsumingEnumerable
1033Channel.CreateBounded
1034Channel.CreateUnbounded
1035Channel bounded full modes
1036ChannelWriter.WriteAsync
1037ChannelWriter.TryWrite
1038ChannelWriter.Complete
1039ChannelReader.ReadAsync
1040ChannelReader.ReadAllAsync
1041ChannelReader.WaitToReadAsync
1042Channel cancellation
1043Channel completion errors
1044SingleReader and SingleWriter options
1045Channel backpressure design
1046Enumerable.Where predicate
1047Enumerable.Where indexed overload
1048Enumerable.Select projection
1049Enumerable.Select indexed overload
1050Enumerable.SelectMany flattening
1051SelectMany result selector
1052Enumerable.OfType
1053Enumerable.Cast
1054Query let clauses
1055Query multiple from clauses
1056Query continuation into
1057Deferred execution and side effects
1058Streaming vs buffering operators
1059Iterator fusion in LINQ
1060LINQ on arrays vs lists
1061IEnumerable vs IQueryable semantics
1062Custom iterator operators
1063Materialization boundaries
1064Multiple enumeration detection
1065TryGetNonEnumeratedCount
1066Enumerable.Order
1067Enumerable.OrderDescending
1068Enumerable.OrderBy
1069Enumerable.OrderByDescending
1070Enumerable.ThenBy
1071Enumerable.ThenByDescending
1072Stable ordering guarantees
1073Enumerable.Reverse
1074Enumerable.GroupBy key selector
1075GroupBy element selector
1076GroupBy result selector
1077GroupBy equality comparer
1078Enumerable.ToLookup
1079ILookup indexing
1080Enumerable.Join
1081Enumerable.GroupJoin
1082Left outer join with DefaultIfEmpty
1083Composite join keys
1084Enumerable.Zip two sequences
1085Enumerable.Zip three sequences
1086Enumerable.Chunk
1087Adjacent grouping custom operator
1088Enumerable.Distinct
1089Enumerable.DistinctBy
1090Enumerable.Union
1091Enumerable.UnionBy
1092Enumerable.Intersect
1093Enumerable.IntersectBy
1094Enumerable.Except
1095Enumerable.ExceptBy
1096Enumerable.Concat
1097Enumerable.Append
1098Enumerable.Prepend
1099Enumerable.Skip
1100Enumerable.Take
1101Enumerable.SkipWhile
1102Enumerable.TakeWhile
1103Enumerable.SkipLast
1104Enumerable.TakeLast
1105Enumerable.Take with Range
1106Enumerable.DefaultIfEmpty
1107Enumerable.Empty
1108Enumerable.Range
1109Enumerable.Repeat
1110Set operators with custom comparers
1111Enumerable.Any
1112Enumerable.All
1113Enumerable.Contains
1114Enumerable.SequenceEqual
1115Enumerable.First
1116Enumerable.FirstOrDefault explicit default
1117Enumerable.Last
1118Enumerable.LastOrDefault
1119Enumerable.Single
1120Enumerable.SingleOrDefault
1121Enumerable.ElementAt
1122Enumerable.ElementAtOrDefault
1123Enumerable.Count
1124Enumerable.LongCount
1125Enumerable.Sum
1126Enumerable.Average
1127Enumerable.Min
1128Enumerable.Max
1129Enumerable.MinBy
1130Enumerable.MaxBy
1131Enumerable.Aggregate seed
1132Aggregate result selector
1133Enumerable.ToList
1134Enumerable.ToArray
1135Enumerable.ToDictionary
1136Enumerable.ToHashSet
1137Numeric overflow in Sum
1138Empty sequence aggregation behavior
1139Queryable expression translation boundaries

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Lesson 1106 of 2,952·9. Collections and LINQ MasteryFree lesson

Enumerable.DefaultIfEmpty

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