HashSet.Add(T) Method

public:
 virtual bool Add(T item);

public:
 bool Add(T item);

public bool Add(T item);

abstract member Add : 'T -> bool
override this.Add : 'T -> bool

member this.Add : 'T -> bool

Public Function Add (item As T) As Boolean

Parameters

Returns

true if the element is added to the HashSet object; false if the element is already present.

Implements

Examples

The following example demonstrates how to create and populate two HashSet objects. This example is part of a larger example provided for the UnionWith method.

HashSet evenNumbers = new HashSet();
HashSet oddNumbers = new HashSet();

for (int i = 0; i < 5; i++)
{
    // Populate numbers with just even numbers.
    evenNumbers.Add(i * 2);

    // Populate oddNumbers with just odd numbers.
    oddNumbers.Add((i * 2) + 1);
}

let evenNumbers = HashSet()
let oddNumbers = HashSet()

for i = 0 to 4 do
    // Populate numbers with just even numbers.
    evenNumbers.Add(i * 2) |> ignore

    // Populate oddNumbers with just odd numbers.
    oddNumbers.Add(i * 2 + 1) |> ignore

Remarks

If Count already equals the capacity of the HashSet object, the capacity is automatically adjusted to accommodate the new item.

If Count is less than the capacity of the internal array, this method is an O(1) operation. If the HashSet object must be resized, this method becomes an O(n) operation, where n is Count.