KeyedCollection<TKey, TItem> Class
Provides the abstract base class for a collection whose keys are embedded in the values.
System.Collections.ObjectModel::Collection<TItem>
System.Collections.ObjectModel::KeyedCollection<TKey, TItem>
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Assembly: mscorlib (in mscorlib.dll)
The KeyedCollection<TKey, TItem> type exposes the following members.
| Name | Description | |
|---|---|---|
![]() ![]() ![]() | KeyedCollection<TKey, TItem>() | Initializes a new instance of the KeyedCollection<TKey, TItem> class that uses the default equality comparer. |
![]() ![]() ![]() | KeyedCollection<TKey, TItem>(IEqualityComparer<TKey>) | Initializes a new instance of the KeyedCollection<TKey, TItem> class that uses the specified equality comparer. |
![]() ![]() ![]() | KeyedCollection<TKey, TItem>(IEqualityComparer<TKey>, Int32) | Initializes a new instance of the KeyedCollection<TKey, TItem> class that uses the specified equality comparer and creates a lookup dictionary when the specified threshold is exceeded. |
| Name | Description | |
|---|---|---|
![]() ![]() ![]() | Comparer | Gets the generic equality comparer that is used to determine equality of keys in the collection. |
![]() ![]() ![]() | Count | Gets the number of elements actually contained in the Collection<T>. (Inherited from Collection<T>.) |
![]() ![]() ![]() | Dictionary | Gets the lookup dictionary of the KeyedCollection<TKey, TItem>. |
![]() ![]() ![]() | Item[TKey] | Gets the element with the specified key. |
![]() ![]() ![]() | Item[Int32] | Gets or sets the element at the specified index. (Inherited from Collection<T>.) |
![]() ![]() ![]() | Items | Gets a IList<T> wrapper around the Collection<T>. (Inherited from Collection<T>.) |
| Name | Description | |
|---|---|---|
![]() ![]() ![]() | Add | Adds an object to the end of the Collection<T>. (Inherited from Collection<T>.) |
![]() ![]() ![]() | ChangeItemKey | Changes the key associated with the specified element in the lookup dictionary. |
![]() ![]() ![]() | Clear | Removes all elements from the Collection<T>. (Inherited from Collection<T>.) |
![]() ![]() ![]() | ClearItems | Removes all elements from the KeyedCollection<TKey, TItem>. (Overrides Collection<T>::ClearItems().) |
![]() ![]() ![]() | Contains(T) | Determines whether an element is in the Collection<T>. (Inherited from Collection<T>.) |
![]() ![]() ![]() | Contains(TKey) | Determines whether the collection contains an element with the specified key. |
![]() ![]() ![]() | CopyTo | Copies the entire Collection<T> to a compatible one-dimensional Array, starting at the specified index of the target array. (Inherited from Collection<T>.) |
![]() ![]() ![]() | Equals(Object) | Determines whether the specified Object is equal to the current Object. (Inherited from Object.) |
![]() ![]() ![]() | Finalize | Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.) |
![]() ![]() ![]() | GetEnumerator | Returns an enumerator that iterates through the Collection<T>. (Inherited from Collection<T>.) |
![]() ![]() ![]() | GetHashCode | Serves as a hash function for a particular type. (Inherited from Object.) |
![]() ![]() ![]() | GetKeyForItem | When implemented in a derived class, extracts the key from the specified element. |
![]() ![]() ![]() | GetType | Gets the Type of the current instance. (Inherited from Object.) |
![]() ![]() ![]() | IndexOf | Searches for the specified object and returns the zero-based index of the first occurrence within the entire Collection<T>. (Inherited from Collection<T>.) |
![]() ![]() ![]() | Insert | Inserts an element into the Collection<T> at the specified index. (Inherited from Collection<T>.) |
![]() ![]() ![]() | InsertItem | Inserts an element into the KeyedCollection<TKey, TItem> at the specified index. (Overrides Collection<T>::InsertItem(Int32, T).) |
![]() ![]() ![]() | MemberwiseClone | Creates a shallow copy of the current Object. (Inherited from Object.) |
![]() ![]() ![]() | Remove(T) | Removes the first occurrence of a specific object from the Collection<T>. (Inherited from Collection<T>.) |
![]() ![]() ![]() | Remove(TKey) | Removes the element with the specified key from the KeyedCollection<TKey, TItem>. |
![]() ![]() ![]() | RemoveAt | Removes the element at the specified index of the Collection<T>. (Inherited from Collection<T>.) |
![]() ![]() ![]() | RemoveItem | Removes the element at the specified index of the KeyedCollection<TKey, TItem>. (Overrides Collection<T>::RemoveItem(Int32).) |
![]() ![]() ![]() | SetItem | Replaces the item at the specified index with the specified item. (Overrides Collection<T>::SetItem(Int32, T).) |
![]() ![]() ![]() | ToString | Returns a string that represents the current object. (Inherited from Object.) |
| Name | Description | |
|---|---|---|
![]() ![]() ![]() ![]() | ICollection::CopyTo | Copies the elements of the ICollection to an Array, starting at a particular Array index. (Inherited from Collection<T>.) |
![]() ![]() ![]() ![]() | ICollection<T>::IsReadOnly | Gets a value indicating whether the ICollection<T> is read-only. (Inherited from Collection<T>.) |
![]() ![]() ![]() ![]() | ICollection::IsSynchronized | Gets a value indicating whether access to the ICollection is synchronized (thread safe). (Inherited from Collection<T>.) |
![]() ![]() ![]() ![]() | ICollection::SyncRoot | Gets an object that can be used to synchronize access to the ICollection. (Inherited from Collection<T>.) |
![]() ![]() ![]() ![]() | IEnumerable::GetEnumerator | Returns an enumerator that iterates through a collection. (Inherited from Collection<T>.) |
![]() ![]() ![]() ![]() | IList::Add | Adds an item to the IList. (Inherited from Collection<T>.) |
![]() ![]() ![]() ![]() | IList::Contains | Determines whether the IList contains a specific value. (Inherited from Collection<T>.) |
![]() ![]() ![]() ![]() | IList::IndexOf | Determines the index of a specific item in the IList. (Inherited from Collection<T>.) |
![]() ![]() ![]() ![]() | IList::Insert | Inserts an item into the IList at the specified index. (Inherited from Collection<T>.) |
![]() ![]() ![]() ![]() | IList::IsFixedSize | Gets a value indicating whether the IList has a fixed size. (Inherited from Collection<T>.) |
![]() ![]() ![]() ![]() | IList::IsReadOnly | Gets a value indicating whether the IList is read-only. (Inherited from Collection<T>.) |
![]() ![]() ![]() ![]() | IList::Item | Gets or sets the element at the specified index. (Inherited from Collection<T>.) |
![]() ![]() ![]() ![]() | IList::Remove | Removes the first occurrence of a specific object from the IList. (Inherited from Collection<T>.) |
The KeyedCollection<TKey, TItem> class provides both O(1) indexed retrieval and keyed retrieval that approaches O(1). It is an abstract type, or more accurately an infinite set of abstract types, because each of its constructed generic types is an abstract base class. To use KeyedCollection<TKey, TItem>, derive your collection type from the appropriate constructed type.
The KeyedCollection<TKey, TItem> class is a hybrid between a collection based on the IList<T> generic interface and a collection based on the IDictionary<TKey, TValue> generic interface. Like collections based on the IList<T> generic interface, KeyedCollection<TKey, TItem> is an indexed list of items. Like collections based on the IDictionary<TKey, TValue> generic interface, KeyedCollection<TKey, TItem> has a key associated with each element.
Unlike dictionaries, an element of KeyedCollection<TKey, TItem> is not a key/value pair; instead, the entire element is the value and the key is embedded within the value. For example, an element of a collection derived from KeyedCollection<String,String> (KeyedCollection(Of String, String) in Visual Basic) might be "John Doe Jr." where the value is "John Doe Jr." and the key is "Doe"; or a collection of employee records containing integer keys could be derived from KeyedCollection<int,Employee>. The abstract GetKeyForItem method extracts the key from the element.
By default, the KeyedCollection<TKey, TItem> includes a lookup dictionary that you can obtain with the Dictionary property. When an item is added to the KeyedCollection<TKey, TItem>, the item's key is extracted once and saved in the lookup dictionary for faster searches. This behavior is overridden by specifying a dictionary creation threshold when you create the KeyedCollection<TKey, TItem>. The lookup dictionary is created the first time the number of elements exceeds that threshold. If you specify –1 as the threshold, the lookup dictionary is never created.
Note |
|---|
When the internal lookup dictionary is used, it contains references to all the items in the collection if TItem is a reference type, or copies of all the items in the collection if TItem is a value type. Thus, using the lookup dictionary may not be appropriate if TItem is a value type. |
You can access an item by its index or key by using the Item property. You can add items without a key, but these items can subsequently be accessed only by index.
This section contains two code examples. The first example shows the minimum code required to derive from KeyedCollection<TKey, TItem>, and demonstrates many of the inherited methods. The second example shows how to override the protected methods of KeyedCollection<TKey, TItem> to provide custom behavior.
Example 1
This code example shows the minimum code necessary to derive a collection class from KeyedCollection<TKey, TItem>: overriding the GetKeyForItem method and providing a public constructor that delegates to a base class constructor. The code example also demonstrates many of the properties and methods inherited from KeyedCollection<TKey, TItem> and Collection<T> classes.
The SimpleOrder class is a very simple requisition list that contains OrderItem objects, each of which represents a line item in the order. The key of OrderItem is immutable, an important consideration for classes that derive from KeyedCollection<TKey, TItem>. For a code example that uses mutable keys, see ChangeItemKey.
using namespace System; using namespace System::Collections::Generic; using namespace System::Collections::ObjectModel; // This class represents a simple line item in an order. All the // values are immutable except quantity. // public ref class OrderItem { private: int _quantity; public: initonly int PartNumber; initonly String^ Description; initonly double UnitPrice; OrderItem(int partNumber, String^ description, int quantity, double unitPrice) { this->PartNumber = partNumber; this->Description = description; this->Quantity = quantity; this->UnitPrice = unitPrice; } property int Quantity { int get() { return _quantity; } void set(int value) { if (value < 0) throw gcnew ArgumentException("Quantity cannot be negative."); _quantity = value; } } virtual String^ ToString() override { return String::Format( "{0,9} {1,6} {2,-12} at {3,8:#,###.00} = {4,10:###,###.00}", PartNumber, _quantity, Description, UnitPrice, UnitPrice * _quantity); } }; // This class represents a very simple keyed list of OrderItems, // inheriting most of its behavior from the KeyedCollection and // Collection classes. The immediate base class is the constructed // type KeyedCollection<int, OrderItem>. When you inherit // from KeyedCollection, the second generic type argument is the // type that you want to store in the collection -- in this case // OrderItem. The first type argument is the type that you want // to use as a key. Its values must be calculated from OrderItem; // in this case it is the int field PartNumber, so SimpleOrder // inherits KeyedCollection<int, OrderItem>. // public ref class SimpleOrder : KeyedCollection<int, OrderItem^> { // The parameterless constructor of the base class creates a // KeyedCollection with an internal dictionary. For this code // example, no other constructors are exposed. // public: SimpleOrder() {} // This is the only method that absolutely must be overridden, // because without it the KeyedCollection cannot extract the // keys from the items. The input parameter type is the // second generic type argument, in this case OrderItem, and // the return value type is the first generic type argument, // in this case int. // protected: virtual int GetKeyForItem(OrderItem^ item) override { // In this example, the key is the part number. return item->PartNumber; } }; public ref class Demo { public: static void Main() { SimpleOrder^ weekly = gcnew SimpleOrder(); // The Add method, inherited from Collection, takes OrderItem. // weekly->Add(gcnew OrderItem(110072674, "Widget", 400, 45.17)); weekly->Add(gcnew OrderItem(110072675, "Sprocket", 27, 5.3)); weekly->Add(gcnew OrderItem(101030411, "Motor", 10, 237.5)); weekly->Add(gcnew OrderItem(110072684, "Gear", 175, 5.17)); Display(weekly); // The Contains method of KeyedCollection takes the key, // type, in this case int. // Console::WriteLine("\nContains(101030411): {0}", weekly->Contains(101030411)); // The default Item property of KeyedCollection takes a key. // Console::WriteLine("\nweekly(101030411)->Description: {0}", weekly[101030411]->Description); // The Remove method of KeyedCollection takes a key. // Console::WriteLine("\nRemove(101030411)"); weekly->Remove(101030411); Display(weekly); // The Insert method, inherited from Collection, takes an // index and an OrderItem. // Console::WriteLine("\nInsert(2, New OrderItem(...))"); weekly->Insert(2, gcnew OrderItem(111033401, "Nut", 10, .5)); Display(weekly); // The default Item property is overloaded. One overload comes // from KeyedCollection<int, OrderItem>; that overload // is read-only, and takes Integer because it retrieves by key. // The other overload comes from Collection<OrderItem>, the // base class of KeyedCollection<int, OrderItem>; it // retrieves by index, so it also takes an Integer. The compiler // uses the most-derived overload, from KeyedCollection, so the // only way to access SimpleOrder by index is to cast it to // Collection<OrderItem>. Otherwise the index is interpreted // as a key, and KeyNotFoundException is thrown. // Collection<OrderItem^>^ coweekly = weekly; Console::WriteLine("\ncoweekly[2].Description: {0}", coweekly[2]->Description); Console::WriteLine("\ncoweekly[2] = gcnew OrderItem(...)"); coweekly[2] = gcnew OrderItem(127700026, "Crank", 27, 5.98); OrderItem^ temp = coweekly[2]; // The IndexOf method inherited from Collection<OrderItem> // takes an OrderItem instead of a key // Console::WriteLine("\nIndexOf(temp): {0}", weekly->IndexOf(temp)); // The inherited Remove method also takes an OrderItem. // Console::WriteLine("\nRemove(temp)"); weekly->Remove(temp); Display(weekly); Console::WriteLine("\nRemoveAt(0)"); weekly->RemoveAt(0); Display(weekly); } private: static void Display(SimpleOrder^ order) { Console::WriteLine(); for each( OrderItem^ item in order ) { Console::WriteLine(item); } } }; void main() { Demo::Main(); } /* This code example produces the following output: 110072674 400 Widget at 45.17 = 18,068.00 110072675 27 Sprocket at 5.30 = 143.10 101030411 10 Motor at 237.50 = 2,375.00 110072684 175 Gear at 5.17 = 904.75 Contains(101030411): True weekly(101030411)->Description: Motor Remove(101030411) 110072674 400 Widget at 45.17 = 18,068.00 110072675 27 Sprocket at 5.30 = 143.10 110072684 175 Gear at 5.17 = 904.75 Insert(2, New OrderItem(...)) 110072674 400 Widget at 45.17 = 18,068.00 110072675 27 Sprocket at 5.30 = 143.10 111033401 10 Nut at .50 = 5.00 110072684 175 Gear at 5.17 = 904.75 coweekly(2)->Description: Nut coweekly[2] = gcnew OrderItem(...) IndexOf(temp): 2 Remove(temp) 110072674 400 Widget at 45.17 = 18,068.00 110072675 27 Sprocket at 5.30 = 143.10 110072684 175 Gear at 5.17 = 904.75 RemoveAt(0) 110072675 27 Sprocket at 5.30 = 143.10 110072684 175 Gear at 5.17 = 904.75 */
Example 2
The following code example shows how to override the protected InsertItem, RemoveItem, ClearItems, and SetItem methods, to provide custom behavior for the Add, Remove, and Clear methods, and for setting the default Item property (the indexer in C#). The custom behavior provided in this example is a notification event named Changed, which is raised at the end of each of the overridden methods.
The code example creates the SimpleOrder class, which derives from KeyedCollection<TKey, TItem> and represents a simple order form. The order form contains OrderItem objects representing items ordered. The code example also creates a SimpleOrderChangedEventArgs class to contain the event information, and an enumeration to identify the type of change.
The code example demonstrates the custom behavior by calling the properties and methods of the derived class, in the Main method of the Demo class.
This code example uses objects with immutable keys. For a code example that uses mutable keys, see ChangeItemKey.
using namespace System; using namespace System::Collections::Generic; using namespace System::Collections::ObjectModel; public enum class ChangeTypes { Added, Removed, Replaced, Cleared }; ref class SimpleOrderChangedEventArgs; // This class represents a simple line item in an order. All the // values are immutable except quantity. // public ref class OrderItem { private: int _quantity; public: initonly int PartNumber; initonly String^ Description; initonly double UnitPrice; OrderItem(int partNumber, String^ description, int quantity, double unitPrice) { this->PartNumber = partNumber; this->Description = description; this->Quantity = quantity; this->UnitPrice = unitPrice; }; property int Quantity { int get() { return _quantity; }; void set(int value) { if (value < 0) throw gcnew ArgumentException("Quantity cannot be negative."); _quantity = value; }; }; virtual String^ ToString() override { return String::Format( "{0,9} {1,6} {2,-12} at {3,8:#,###.00} = {4,10:###,###.00}", PartNumber, _quantity, Description, UnitPrice, UnitPrice * _quantity); }; }; // Event argument for the Changed event. // public ref class SimpleOrderChangedEventArgs : EventArgs { public: OrderItem^ ChangedItem; initonly ChangeTypes ChangeType; OrderItem^ ReplacedWith; SimpleOrderChangedEventArgs(ChangeTypes change, OrderItem^ item, OrderItem^ replacement) { this->ChangeType = change; this->ChangedItem = item; this->ReplacedWith = replacement; } }; // This class derives from KeyedCollection and shows how to override // the protected ClearItems, InsertItem, RemoveItem, and SetItem // methods in order to change the behavior of the default Item // property and the Add, Clear, Insert, and Remove methods. The // class implements a Changed event, which is raised by all the // protected methods. // // SimpleOrder is a collection of OrderItem objects, and its key // is the PartNumber field of OrderItem-> PartNumber is an Integer, // so SimpleOrder inherits KeyedCollection<int, OrderItem>. // (Note that the key of OrderItem cannot be changed; if it could // be changed, SimpleOrder would have to override ChangeItemKey.) // public ref class SimpleOrder : KeyedCollection<int, OrderItem^> { public: event EventHandler<SimpleOrderChangedEventArgs^>^ Changed; // This parameterless constructor calls the base class constructor // that specifies a dictionary threshold of 0, so that the internal // dictionary is created as soon as an item is added to the // collection. // SimpleOrder() : KeyedCollection<int, OrderItem^>(nullptr, 0) {}; // This is the only method that absolutely must be overridden, // because without it the KeyedCollection cannot extract the // keys from the items. // protected: virtual int GetKeyForItem(OrderItem^ item) override { // In this example, the key is the part number. return item->PartNumber; } virtual void InsertItem(int index, OrderItem^ newItem) override { __super::InsertItem(index, newItem); Changed(this, gcnew SimpleOrderChangedEventArgs( ChangeTypes::Added, newItem, nullptr)); } virtual void SetItem(int index, OrderItem^ newItem) override { OrderItem^ replaced = this->Items[index]; __super::SetItem(index, newItem); Changed(this, gcnew SimpleOrderChangedEventArgs( ChangeTypes::Replaced, replaced, newItem)); } virtual void RemoveItem(int index) override { OrderItem^ removedItem = Items[index]; __super::RemoveItem(index); Changed(this, gcnew SimpleOrderChangedEventArgs( ChangeTypes::Removed, removedItem, nullptr)); } virtual void ClearItems() override { __super::ClearItems(); Changed(this, gcnew SimpleOrderChangedEventArgs( ChangeTypes::Cleared, nullptr, nullptr)); } // This method uses the internal reference to the dictionary // to test fo public: void AddOrMerge(OrderItem^ newItem) { int key = this->GetKeyForItem(newItem); OrderItem^ existingItem = nullptr; // The dictionary is not created until the first item is // added, so it is necessary to test for null. Using // AndAlso ensures that TryGetValue is not called if the // dictionary does not exist. // if (this->Dictionary != nullptr && this->Dictionary->TryGetValue(key, existingItem)) { existingItem->Quantity += newItem->Quantity; } else { this->Add(newItem); } } }; public ref class Demo { public: static void Main() { SimpleOrder^ weekly = gcnew SimpleOrder(); weekly->Changed += gcnew EventHandler<SimpleOrderChangedEventArgs^>(ChangedHandler); // The Add method, inherited from Collection, takes OrderItem-> // weekly->Add(gcnew OrderItem(110072674, "Widget", 400, 45.17)); weekly->Add(gcnew OrderItem(110072675, "Sprocket", 27, 5.3)); weekly->Add(gcnew OrderItem(101030411, "Motor", 10, 237.5)); weekly->Add(gcnew OrderItem(110072684, "Gear", 175, 5.17)); Display(weekly); // The Contains method of KeyedCollection takes TKey. // Console::WriteLine("\nContains(101030411): {0}", weekly->Contains(101030411)); // The default Item property of KeyedCollection takes the key // type, Integer. The property is read-only. // Console::WriteLine("\nweekly[101030411]->Description: {0}", weekly[101030411]->Description); // The Remove method of KeyedCollection takes a key. // Console::WriteLine("\nRemove(101030411)"); weekly->Remove(101030411); // The Insert method, inherited from Collection, takes an // index and an OrderItem. // Console::WriteLine("\nInsert(2, gcnew OrderItem(...))"); weekly->Insert(2, gcnew OrderItem(111033401, "Nut", 10, .5)); // The default Item property is overloaded. One overload comes // from KeyedCollection<int, OrderItem>; that overload // is read-only, and takes Integer because it retrieves by key. // The other overload comes from Collection<OrderItem>, the // base class of KeyedCollection<int, OrderItem>; it // retrieves by index, so it also takes an Integer. The compiler // uses the most-derived overload, from KeyedCollection, so the // only way to access SimpleOrder by index is to cast it to // Collection<OrderItem>. Otherwise the index is interpreted // as a key, and KeyNotFoundException is thrown. // Collection<OrderItem^>^ coweekly = weekly; Console::WriteLine("\ncoweekly[2].Description: {0}", coweekly[2]->Description); Console::WriteLine("\ncoweekly[2] = gcnew OrderItem(...)"); coweekly[2] = gcnew OrderItem(127700026, "Crank", 27, 5.98); OrderItem^ temp = coweekly[2]; // The IndexOf method, inherited from Collection<OrderItem>, // takes an OrderItem instead of a key. // Console::WriteLine("\nIndexOf(temp): {0}", weekly->IndexOf(temp)); // The inherited Remove method also takes an OrderItem-> // Console::WriteLine("\nRemove(temp)"); weekly->Remove(temp); Console::WriteLine("\nRemoveAt(0)"); weekly->RemoveAt(0); weekly->AddOrMerge(gcnew OrderItem(110072684, "Gear", 1000, 5.17)); Display(weekly); Console::WriteLine(); weekly->Clear(); } private: static void Display(SimpleOrder^ order) { Console::WriteLine(); for each( OrderItem^ item in order ) { Console::WriteLine(item); } } static void ChangedHandler(Object^ source, SimpleOrderChangedEventArgs^ e) { OrderItem^ item = e->ChangedItem; if (e->ChangeType == ChangeTypes::Replaced) { OrderItem^ replacement = e->ReplacedWith; Console::WriteLine("{0} (quantity {1}) was replaced " + "by {2}, (quantity {3}).", item->Description, item->Quantity, replacement->Description, replacement->Quantity); } else if(e->ChangeType == ChangeTypes::Cleared) { Console::WriteLine("The order list was cleared."); } else { Console::WriteLine("{0} (quantity {1}) was {2}.", item->Description, item->Quantity, e->ChangeType); } } }; void main() { Demo::Main(); } /* This code example produces the following output: Widget (quantity 400) was Added. Sprocket (quantity 27) was Added. Motor (quantity 10) was Added. Gear (quantity 175) was Added. 110072674 400 Widget at 45.17 = 18,068.00 110072675 27 Sprocket at 5.30 = 143.10 101030411 10 Motor at 237.50 = 2,375.00 110072684 175 Gear at 5.17 = 904.75 Contains(101030411): True weekly[101030411]->Description: Motor Remove(101030411) Motor (quantity 10) was Removed. Insert(2, gcnew OrderItem(...)) Nut (quantity 10) was Added. coweekly[2].Description: Nut coweekly[2] = gcnew OrderItem(...) Nut (quantity 10) was replaced by Crank, (quantity 27). IndexOf(temp): 2 Remove(temp) Crank (quantity 27) was Removed. RemoveAt(0) Widget (quantity 400) was Removed. 110072675 27 Sprocket at 5.30 = 143.10 110072684 1175 Gear at 5.17 = 6,074.75 The order list was cleared. */
Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
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