HashSet<T>.Clear Metode

Definisi

Ruang nama:

System.Collections.Generic

Rakitan:

System.Collections.dll

Sumber:

HashSet.cs

Menghapus semua elemen dari HashSet<T> objek.

public:
 virtual void Clear();

public void Clear ();

abstract member Clear : unit -> unit
override this.Clear : unit -> unit

Public Sub Clear ()

Penerapan

Clear()

Contoh

Contoh berikut membuat dan mengisi HashSet<T> koleksi, lalu menghapusnya dan merilis memori yang dirujuk oleh koleksi.

HashSet<int> Numbers = new HashSet<int>();

for (int i = 0; i < 10; i++)
{
    Numbers.Add(i);
}

Console.Write("Numbers contains {0} elements: ", Numbers.Count);
DisplaySet(Numbers);

Numbers.Clear();
Numbers.TrimExcess();

Console.Write("Numbers contains {0} elements: ", Numbers.Count);
DisplaySet(Numbers);

void DisplaySet(HashSet<int> set)
{
    Console.Write("{");
    foreach (int i in set)
    {
        Console.Write(" {0}", i);
    }
    Console.WriteLine(" }");
}

/* This example produces output similar to the following:
* Numbers contains 10 elements: { 0 1 2 3 4 5 6 7 8 9 }
* Numbers contains 0 elements: { }
*/

Imports System.Collections.Generic

Class Program

    Shared Sub Main()

        Dim Numbers As HashSet(Of Integer) = New HashSet(Of Integer)()

        For i As Integer = 0 To 9
            Numbers.Add(i)
        Next i

        Console.Write("Numbers contains {0} elements: ", Numbers.Count)
        DisplaySet(Numbers)

        Numbers.Clear()
        Numbers.TrimExcess()

        Console.Write("Numbers contains {0} elements: ", Numbers.Count)
        DisplaySet(Numbers)

    End Sub
    ' This code example produces output similar to the following:
    ' Numbers contains 10 elements: { 0 1 2 3 4 5 6 7 8 9 }
    ' Numbers contains 0 elements: { }

    Private Shared Sub DisplaySet(ByVal coll As HashSet(Of Integer))
        Console.Write("{")
        For Each i As Integer In coll
            Console.Write(" {0}", i)
        Next i
        Console.WriteLine(" }")
    End Sub

End Class

Keterangan

Count diatur ke nol dan referensi ke objek lain dari elemen koleksi juga dirilis. Kapasitas tetap tidak berubah sampai panggilan ke TrimExcess dilakukan.

Metode ini adalah operasi O(n), di mana n adalah Count.