HashSet<T>.UnionWith(IEnumerable<T>) 方法

定义

命名空间:

System.Collections.Generic

程序集:

System.Collections.dll

Source:

HashSet.cs

修改当前 HashSet<T> 对象以包含存在于该对象中、指定集合中或两者中的所有元素。

public:
 virtual void UnionWith(System::Collections::Generic::IEnumerable<T> ^ other);

public void UnionWith (System.Collections.Generic.IEnumerable<T> other);

abstract member UnionWith : seq<'T> -> unit
override this.UnionWith : seq<'T> -> unit

Public Sub UnionWith (other As IEnumerable(Of T))

参数

other

IEnumerable<T>

要与当前的 HashSet<T> 对象进行比较的集合。

实现

UnionWith(IEnumerable<T>)

例外

ArgumentNullException

other 为 null。

示例

以下示例演示如何合并两个不同的集。 此示例创建两个 HashSet<T> 对象，并分别使用偶数和奇数填充它们。 第三 HashSet<T> 个 对象是从包含偶数的集中创建的。 然后，该示例调用 UnionWith 方法，该方法将奇数集添加到第三组。

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);
}

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

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

// Create a new HashSet populated with even numbers.
HashSet<int> numbers = new HashSet<int>(evenNumbers);
Console.WriteLine("numbers UnionWith oddNumbers...");
numbers.UnionWith(oddNumbers);

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

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

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

Imports System.Collections.Generic

Class Program

    Shared Sub Main()

        Dim evenNumbers As HashSet(Of Integer) = New HashSet(Of Integer)()
        Dim oddNumbers As HashSet(Of Integer) = New HashSet(Of Integer)()

        For i As Integer = 0 To 4

            ' Populate evenNumbers with only even numbers.
            evenNumbers.Add(i * 2)

            ' Populate oddNumbers with only odd numbers.
            oddNumbers.Add((i * 2) + 1)
        Next i

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

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

        ' Create a new HashSet populated with even numbers.
        Dim numbers As HashSet(Of Integer) = New HashSet(Of Integer)(evenNumbers)
        Console.WriteLine("numbers UnionWith oddNumbers...")
        numbers.UnionWith(oddNumbers)

        Console.Write("numbers contains {0} elements: ", numbers.Count)
        DisplaySet(numbers)
    End Sub


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

End Class
' This example produces output similar to the following:
' evenNumbers contains 5 elements: { 0 2 4 6 8 }
' oddNumbers contains 5 elements: { 1 3 5 7 9 }
' numbers UnionWith oddNumbers...
' numbers contains 10 elements: { 0 2 4 6 8 1 3 5 7 9 }

注解

此方法是 O (n) 操作，其中 n 是 参数中的 other 元素数。