Struct UnsafeMultiHashMap<TKey, TValue>

An unordered, expandable associative array. Each key can have more than one associated value.

Implements

INativeDisposable

Namespace: Unity.Collections.LowLevel.Unsafe

Assembly: Unity.Collections.dll

Syntax

public struct UnsafeMultiHashMap<TKey, TValue> : INativeDisposable where TKey : struct, IEquatable<TKey> where TValue : struct

Type Parameters

Name	Description
TKey	The type of the keys.
TValue	The type of the values.

Remarks

Unlike a regular UnsafeHashMap, an UnsafeMultiHashMap can store multiple key-value pairs with the same key.

The keys are not deduplicated: two key-value pairs with the same key are stored as fully separate key-value pairs.

Constructors

UnsafeMultiHashMap(int, AllocatorHandle)

Initializes and returns an instance of UnsafeMultiHashMap.

Declaration

public UnsafeMultiHashMap(int capacity, AllocatorManager.AllocatorHandle allocator)

Parameters

Type	Name	Description
int	capacity	The number of key-value pairs that should fit in the initial allocation.
AllocatorManager.AllocatorHandle	allocator	The allocator to use.

Properties

Capacity

Returns the number of key-value pairs that fit in the current allocation.

Declaration

public int Capacity { get; set; }

Property Value

Type	Description
int	The number of key-value pairs that fit in the current allocation.

Exceptions

Type	Condition
Exception	Thrown if value is less than the current capacity.

IsCreated

Whether this hash map has been allocated (and not yet deallocated).

Declaration

public bool IsCreated { get; }

Property Value

Type	Description
bool	True if this hash map has been allocated (and not yet deallocated).

IsEmpty

Whether this hash map is empty.

Declaration

public bool IsEmpty { get; }

Property Value

Type	Description
bool	True if this hash map is empty.

Methods

Add(TKey, TValue)

Adds a new key-value pair.

Declaration

public void Add(TKey key, TValue item)

Parameters

Type	Name	Description
TKey	key	The key to add.
TValue	item	The value to add.

Remarks

If a key-value pair with this key is already present, an additional separate key-value pair is added.

AsParallelWriter()

Returns a parallel writer for this hash map.

Declaration

public UnsafeMultiHashMap<TKey, TValue>.ParallelWriter AsParallelWriter()

Returns

Type	Description
UnsafeMultiHashMap<TKey, TValue>.ParallelWriter	A parallel writer for this hash map.

Clear()

Removes all key-value pairs.

Declaration

public void Clear()

Remarks

Does not change the capacity.

ContainsKey(TKey)

Returns true if a given key is present in this hash map.

Declaration

public bool ContainsKey(TKey key)

Parameters

Type	Name	Description
TKey	key	The key to look up.

Returns

Type	Description
bool	True if the key was present in this hash map.

Count()

Returns the current number of key-value pairs in this hash map.

Declaration

public int Count()

Returns

Type	Description
int	The current number of key-value pairs in this hash map.

Remarks

Key-value pairs with matching keys are counted as separate, individual pairs.

CountValuesForKey(TKey)

Returns the number of values associated with a given key.

Declaration

public int CountValuesForKey(TKey key)

Parameters

Type	Name	Description
TKey	key	The key to look up.

Returns

Type	Description
int	The number of values associated with the key. Returns 0 if the key was not present.

Dispose()

Releases all resources (memory and safety handles).

Declaration

public void Dispose()

Dispose(JobHandle)

Creates and schedules a job that will dispose this hash map.

Declaration

public JobHandle Dispose(JobHandle inputDeps)

Parameters

Type	Name	Description
JobHandle	inputDeps	A job handle. The newly scheduled job will depend upon this handle.

Returns

Type	Description
JobHandle	The handle of a new job that will dispose this hash map.

GetEnumerator()

Returns an enumerator over the key-value pairs of this hash map.

Declaration

public UnsafeMultiHashMap<TKey, TValue>.KeyValueEnumerator GetEnumerator()

Returns

Type	Description
UnsafeMultiHashMap<TKey, TValue>.KeyValueEnumerator	An enumerator over the key-value pairs of this hash map.

Remarks

A key with N values is visited by the enumerator N times.

GetKeyArray(AllocatorHandle)

Returns an array with a copy of all the keys (in no particular order).

Declaration

public NativeArray<TKey> GetKeyArray(AllocatorManager.AllocatorHandle allocator)

Parameters

Type	Name	Description
AllocatorManager.AllocatorHandle	allocator	The allocator to use.

Returns

Type	Description
NativeArray<TKey>	An array with a copy of all the keys (in no particular order).

Remarks

A key with N values is included N times in the array.

 Use `GetUniqueKeyArray` of <xref href="Unity.Collections.NativeHashMapExtensions" data-throw-if-not-resolved="false"></xref> instead if you only want one occurrence of each key.

GetKeyValueArrays(AllocatorHandle)

Returns a NativeKeyValueArrays with a copy of all the keys and values (in no particular order).

Declaration

public NativeKeyValueArrays<TKey, TValue> GetKeyValueArrays(AllocatorManager.AllocatorHandle allocator)

Parameters

Type	Name	Description
AllocatorManager.AllocatorHandle	allocator	The allocator to use.

Returns

Type	Description
NativeKeyValueArrays<TKey, TValue>	A NativeKeyValueArrays with a copy of all the keys and values (in no particular order).

Remarks

A key with N values is included N times in the array.

GetValueArray(AllocatorHandle)

Returns an array with a copy of all the values (in no particular order).

Declaration

public NativeArray<TValue> GetValueArray(AllocatorManager.AllocatorHandle allocator)

Parameters

Type	Name	Description
AllocatorManager.AllocatorHandle	allocator	The allocator to use.

Returns

Type	Description
NativeArray<TValue>	An array with a copy of all the values (in no particular order).

Remarks

The values are not deduplicated. If you sort the returned array, you can use Unique<T>(NativeArray<T>) to remove duplicate values.

GetValuesForKey(TKey)

Returns an enumerator over the values of an individual key.

Declaration

public UnsafeMultiHashMap<TKey, TValue>.Enumerator GetValuesForKey(TKey key)

Parameters

Type	Name	Description
TKey	key	The key to get an enumerator for.

Returns

Type	Description
UnsafeMultiHashMap<TKey, TValue>.Enumerator	An enumerator over the values of a key.

Remove(NativeMultiHashMapIterator<TKey>)

Removes a single key-value pair.

Declaration

public void Remove(NativeMultiHashMapIterator<TKey> it)

Parameters

Type	Name	Description
NativeMultiHashMapIterator<TKey>	it	An iterator representing the key-value pair to remove.

Exceptions

Type	Condition
InvalidOperationException	Thrown if the iterator is invalid.

Remove(TKey)

Removes a key and its associated value(s).

Declaration

public int Remove(TKey key)

Parameters

Type	Name	Description
TKey	key	The key to remove.

Returns

Type	Description
int	The number of removed key-value pairs. If the key was not present, returns 0.

Remove<TValueEQ>(TKey, TValueEQ)

Removes all key-value pairs with a particular key and a particular value.

Declaration

public void Remove<TValueEQ>(TKey key, TValueEQ value) where TValueEQ : struct, IEquatable<TValueEQ>

Parameters

Type	Name	Description
TKey	key	The key of the key-value pairs to remove.
TValueEQ	value	The value of the key-value pairs to remove.

Type Parameters

Name	Description
TValueEQ	The type of the value.

Remarks

Removes all key-value pairs which have a particular key and which also have a particular value. In other words: (key AND value) rather than (key OR value).

SetValue(TValue, NativeMultiHashMapIterator<TKey>)

Sets a new value for an existing key-value pair.

Declaration

public bool SetValue(TValue item, NativeMultiHashMapIterator<TKey> it)

Parameters

Type	Name	Description
TValue	item	The new value.
NativeMultiHashMapIterator<TKey>	it	The iterator representing a key-value pair.

Returns

Type	Description
bool	True if a value was overwritten.

TryGetFirstValue(TKey, out TValue, out NativeMultiHashMapIterator<TKey>)

Gets an iterator for a key.

Declaration

public bool TryGetFirstValue(TKey key, out TValue item, out NativeMultiHashMapIterator<TKey> it)

Parameters

Type	Name	Description
TKey	key	The key.
TValue	item	Outputs the associated value represented by the iterator.
NativeMultiHashMapIterator<TKey>	it	Outputs an iterator.

Returns

Type	Description
bool	True if the key was present.

TryGetNextValue(out TValue, ref NativeMultiHashMapIterator<TKey>)

Advances an iterator to the next value associated with its key.

Declaration

public bool TryGetNextValue(out TValue item, ref NativeMultiHashMapIterator<TKey> it)

Parameters

Type	Name	Description
TValue	item	Outputs the next value.
NativeMultiHashMapIterator<TKey>	it	A reference to the iterator to advance.

Returns

Type	Description
bool	True if the key was present and had another value.

Implements

INativeDisposable