HashSet<T>.Add(T) Method
Definition
Important
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Adds the specified element to a set.
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 -> boolmember this.Add : 'T -> boolPublic Function Add (item As T) As BooleanParameters
- item
- T
The element to add to the set.
Returns
true if the element is added to the HashSet<T> object; false if the element is already present.
Implements
Examples
The following example demonstrates how to create and populate two HashSet<T> objects. This example is part of a larger example provided for the UnionWith method.
HashSet<int> evenNumbers = new HashSet<int>();
HashSet<int> oddNumbers = new HashSet<int>();
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<int>()
let oddNumbers = HashSet<int>()
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<T> 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<T> object must be resized, this method becomes an O(n) operation, where n is Count.
