Namespace: System.Collections.Generic
Dictionary<TKey, TValue>
Represents a collection of keys and values.
Properties (3)
int Count
Gets the number of key/value pairs contained in the Dictionary.
Value: The number of key/value pairs contained in the Dictionary.
KeyCollection<TKey, TValue> Keys
Gets a collection containing the keys in the Dictionary.
Value: A KeyCollection containing the keys in the Dictionary.
TValue Item(T)
Gets or sets the value associated with the specified key.
Value: The value associated with the specified key. If the specified key is not found, a get operation throws a KeyNotFoundException, and a set operation creates a new element with the specified key.
Methods (9)
Dictionary<TKey, TValue>(Int32)Constructor
Initializes a new instance of the Dictionary class that is empty, has the specified initial capacity, and uses the default equality comparer for the key type.
| Parameter | Description |
|---|---|
| capacity | The initial number of elements that the Dictionary can contain. |
Dictionary<TKey, TValue>(Int32,IEqualityComparer<T>)Constructor
Initializes a new instance of the Dictionary class that is empty, has the specified initial capacity, and uses the specified IEqualityComparer.
| Parameter | Description |
|---|---|
| capacity | The initial number of elements that the Dictionary can contain. |
| comparer | The IEqualityComparer implementation to use when comparing keys, or null to use the default EqualityComparer for the type of the key. |
Dictionary<TKey, TValue>(IEqualityComparer<T>)Constructor
Initializes a new instance of the Dictionary class that is empty, has the default initial capacity, and uses the specified IEqualityComparer.
| Parameter | Description |
|---|---|
| comparer | The IEqualityComparer implementation to use when comparing keys, or null to use the default EqualityComparer for the type of the key. |
void Add(T,TValue)
Adds the specified key and value to the dictionary.
| Parameter | Description |
|---|---|
| key | The key of the element to add. |
| value | The value of the element to add. The value can be null for reference types. |
bool TryGetValue(T,TValue@)
Gets the value associated with the specified key.
| Parameter | Description |
|---|---|
| key | The key of the value to get. |
| value | When this method returns, contains the value associated with the specified key, if the key is found; otherwise, the default value for the type of the value parameter. This parameter is passed uninitialized. |
Returns: true if the Dictionary contains an element with the specified key; otherwise, false.
bool ContainsKey(T)
Determines whether the Dictionary contains the specified key.
| Parameter | Description |
|---|---|
| key | The key to locate in the Dictionary. |
Returns: true if the Dictionary contains an element with the specified key; otherwise, false.
bool Remove(T)
Removes the value with the specified key from the Dictionary.
| Parameter | Description |
|---|---|
| key | The key of the element to remove. |
Returns: true if the element is successfully found and removed; otherwise, false. This method returns false if key is not found in the Dictionary.
void Clear
Removes all keys and values from the Dictionary.
Enumerator<TKey, TValue> GetEnumerator
Returns an enumerator that iterates through the Dictionary.
Returns: A Enumerator structure for the Dictionary.