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class System.​Collections.​Generic.​Dictionary<​TKey, TValue>

Assembly: System.Collections

Inheritance: object → Dictionary

Implemented Interfaces

Represents a collection of keys and values.

Properties

public IEqualityComparer<​TKey>
Comparer
Gets the <see cref="T:System.Collections.Generic.IEqualityComparer`1" /> that is used to determine equality of keys for the dictionary.
public int
Count
Gets the number of key/value pairs contained in the <see cref="T:System.Collections.Generic.Dictionary`2" /> .
public int
Capacity
Gets the total numbers of elements the internal data structure can hold without resizing.
public TValue
Item
public KeyCollection<​TKey, TValue>
Keys
Gets a collection containing the keys in the <see cref="T:System.Collections.Generic.Dictionary`2" /> .
public ValueCollection<​TKey, TValue>
Values
Gets a collection containing the values in the <see cref="T:System.Collections.Generic.Dictionary`2" /> .

Methods

public void
Add​(TKey key, TValue value)
Adds the specified key and value to the dictionary.
key The key of the element to add.
value The value of the element to add. The value can be <see langword="null" /> for reference types.
public void
Clear​()
Removes all keys and values from the <see cref="T:System.Collections.Generic.Dictionary`2" /> .
public bool
ContainsKey​(TKey key)
Determines whether the <see cref="T:System.Collections.Generic.Dictionary`2" /> contains the specified key.
Returns <see langword="true" /> if the <see cref="T:System.Collections.Generic.Dictionary`2" /> contains an element with the specified key; otherwise, <see langword="false" /> .
key The key to locate in the <see cref="T:System.Collections.Generic.Dictionary`2" /> .
public bool
ContainsValue​(TValue value)
Determines whether the <see cref="T:System.Collections.Generic.Dictionary`2" /> contains a specific value.
Returns <see langword="true" /> if the <see cref="T:System.Collections.Generic.Dictionary`2" /> contains an element with the specified value; otherwise, <see langword="false" /> .
value The value to locate in the <see cref="T:System.Collections.Generic.Dictionary`2" /> . The value can be <see langword="null" /> for reference types.
public int
EnsureCapacity​(int capacity)
Ensures that the dictionary can hold up to a specified number of entries without any further expansion of its backing storage.
Returns The current capacity of the <see cref="T:System.Collections.Generic.Dictionary`2" /> .
capacity The number of entries.
public AlternateLookup<​TKey, TValue, TAlternateKey>
GetAlternateLookup​()
Gets an instance of a type that can be used to perform operations on the current <see cref="T:System.Collections.Generic.Dictionary`2" /> using a <typeparamref name="TAlternateKey" /> as a key instead of a <typeparamref name="TKey" /> .
Returns The created lookup instance.
public Enumerator<​TKey, TValue>
GetEnumerator​()
Returns an enumerator that iterates through the <see cref="T:System.Collections.Generic.Dictionary`2" /> .
Returns A <see cref="T:System.Collections.Generic.Dictionary`2.Enumerator" /> structure for the <see cref="T:System.Collections.Generic.Dictionary`2" /> .
public void
GetObjectData​(Runtime.​Serialization.​SerializationInfo info, Runtime.​Serialization.​StreamingContext context)
Implements the <see cref="T:System.Runtime.Serialization.ISerializable" /> interface and returns the data needed to serialize the <see cref="T:System.Collections.Generic.Dictionary`2" /> instance.
info A <see cref="T:System.Runtime.Serialization.SerializationInfo" /> object that contains the information required to serialize the <see cref="T:System.Collections.Generic.Dictionary`2" /> instance.
context A <see cref="T:System.Runtime.Serialization.StreamingContext" /> structure that contains the source and destination of the serialized stream associated with the <see cref="T:System.Collections.Generic.Dictionary`2" /> instance.
public void
OnDeserialization​(object sender)
Implements the <see cref="T:System.Runtime.Serialization.ISerializable" /> interface and raises the deserialization event when the deserialization is complete.
sender The source of the deserialization event.
public bool
Remove​(TKey key)
Removes the value with the specified key from the <see cref="T:System.Collections.Generic.Dictionary`2" /> .
Returns <see langword="true" /> if the element is successfully found and removed; otherwise, <see langword="false" /> . This method returns <see langword="false" /> if <paramref name="key" /> is not found in the <see cref="T:System.Collections.Generic.Dictionary`2" /> .
key The key of the element to remove.
public bool
Remove​(TKey key, TValue& value)
public void
TrimExcess​()
Sets the capacity of this dictionary to what it would be if it had been originally initialized with all its entries.
public void
TrimExcess​(int capacity)
Sets the capacity of this dictionary to hold up a specified number of entries without any further expansion of its backing storage.
capacity The new capacity.
public bool
TryAdd​(TKey key, TValue value)
Attempts to add the specified key and value to the dictionary.
Returns <see langword="true" /> if the key/value pair was added to the dictionary successfully; otherwise, <see langword="false" /> .
key The key of the element to add.
value The value of the element to add. It can be <see langword="null" /> .
public bool
TryGetAlternateLookup​(AlternateLookup`1& lookup)
public bool
TryGetValue​(TKey key, TValue& value)
public bool
Equals​(object obj)
Inherited from object
protected void
Finalize​()
Inherited from object
public int
GetHashCode​()
Inherited from object
public Type
GetType​()
Inherited from object
protected object
MemberwiseClone​()
Inherited from object
public string
ToString​()
Inherited from object