HashSet C#（對於開發者的運行原理）

using System;
using System.Collections.Generic;

class Program
{
    static void Main()
    {
        // Initializes a HashSet of integers
        HashSet<int> numbers = new HashSet<int>();

        // Adds elements to the HashSet
        numbers.Add(1);
        numbers.Add(2);
        numbers.Add(3);

        // Removes an element from the HashSet
        numbers.Remove(2);

        // Checks for membership of an element
        bool containsThree = numbers.Contains(3);

        Console.WriteLine($"Contains 3: {containsThree}");
    }
}

Imports System
Imports System.Collections.Generic

Friend Class Program
	Shared Sub Main()
		' Initializes a HashSet of integers
		Dim numbers As New HashSet(Of Integer)()

		' Adds elements to the HashSet
		numbers.Add(1)
		numbers.Add(2)
		numbers.Add(3)

		' Removes an element from the HashSet
		numbers.Remove(2)

		' Checks for membership of an element
		Dim containsThree As Boolean = numbers.Contains(3)

		Console.WriteLine($"Contains 3: {containsThree}")
	End Sub
End Class

using System;
using System.Collections.Generic;

class Program
{
    static void Main()
    {
        // Creates a list with duplicate elements
        List<int> duplicateNumbers = new List<int> { 1, 2, 2, 3, 3, 4 };

        // Initializes a HashSet with the list, automatically removes duplicates
        HashSet<int> uniqueNumbers = new HashSet<int>(duplicateNumbers);

        Console.WriteLine("Unique numbers:");
        foreach (var number in uniqueNumbers)
        {
            Console.WriteLine(number);
        }
    }
}

Imports System
Imports System.Collections.Generic

Friend Class Program
	Shared Sub Main()
		' Creates a list with duplicate elements
		Dim duplicateNumbers As New List(Of Integer) From {1, 2, 2, 3, 3, 4}

		' Initializes a HashSet with the list, automatically removes duplicates
		Dim uniqueNumbers As New HashSet(Of Integer)(duplicateNumbers)

		Console.WriteLine("Unique numbers:")
		For Each number In uniqueNumbers
			Console.WriteLine(number)
		Next number
	End Sub
End Class

using System;
using System.Collections.Generic;

class Program
{
    static void Main()
    {
        HashSet<int> set1 = new HashSet<int> { 1, 2, 3 };
        HashSet<int> set2 = new HashSet<int> { 3, 4, 5 };

        // Merges set2 into set1
        set1.UnionWith(set2);

        Console.WriteLine("Union of set1 and set2:");
        foreach (var item in set1)
        {
            Console.WriteLine(item);
        }
    }
}

Imports System
Imports System.Collections.Generic

Friend Class Program
	Shared Sub Main()
		Dim set1 As New HashSet(Of Integer) From {1, 2, 3}
		Dim set2 As New HashSet(Of Integer) From {3, 4, 5}

		' Merges set2 into set1
		set1.UnionWith(set2)

		Console.WriteLine("Union of set1 and set2:")
		For Each item In set1
			Console.WriteLine(item)
		Next item
	End Sub
End Class

using System;
using System.Collections.Generic;

class Program
{
    static void Main()
    {
        HashSet<int> set1 = new HashSet<int> { 1, 2, 3 };
        HashSet<int> set2 = new HashSet<int> { 3, 4, 5 };

        // Keeps only elements that are present in both sets
        set1.IntersectWith(set2);

        Console.WriteLine("Intersection of set1 and set2:");
        foreach (var item in set1)
        {
            Console.WriteLine(item);
        }
    }
}

Imports System
Imports System.Collections.Generic

Friend Class Program
	Shared Sub Main()
		Dim set1 As New HashSet(Of Integer) From {1, 2, 3}
		Dim set2 As New HashSet(Of Integer) From {3, 4, 5}

		' Keeps only elements that are present in both sets
		set1.IntersectWith(set2)

		Console.WriteLine("Intersection of set1 and set2:")
		For Each item In set1
			Console.WriteLine(item)
		Next item
	End Sub
End Class

using System;
using System.Collections.Generic;

class Program
{
    static void Main()
    {
        HashSet<int> set1 = new HashSet<int> { 1, 2, 3 };
        HashSet<int> set2 = new HashSet<int> { 3, 4, 5 };

        // Removes elements from set1 that are also in set2
        set1.ExceptWith(set2);

        Console.WriteLine("Difference of set1 and set2:");
        foreach (var item in set1)
        {
            Console.WriteLine(item);
        }
    }
}

Imports System
Imports System.Collections.Generic

Friend Class Program
	Shared Sub Main()
		Dim set1 As New HashSet(Of Integer) From {1, 2, 3}
		Dim set2 As New HashSet(Of Integer) From {3, 4, 5}

		' Removes elements from set1 that are also in set2
		set1.ExceptWith(set2)

		Console.WriteLine("Difference of set1 and set2:")
		For Each item In set1
			Console.WriteLine(item)
		Next item
	End Sub
End Class

using System;
using System.Collections.Generic;

class Program
{
    static void Main()
    {
        HashSet<int> set1 = new HashSet<int> { 1, 2, 3 };
        HashSet<int> set2 = new HashSet<int> { 2, 3 };

        // Checks if set2 is a subset of set1
        bool isSubset = set2.IsSubsetOf(set1);

        // Checks if set1 is a superset of set2
        bool isSuperset = set1.IsSupersetOf(set2);

        Console.WriteLine($"Is set2 a subset of set1: {isSubset}");
        Console.WriteLine($"Is set1 a superset of set2: {isSuperset}");
    }
}

Imports System
Imports System.Collections.Generic

Friend Class Program
	Shared Sub Main()
		Dim set1 As New HashSet(Of Integer) From {1, 2, 3}
		Dim set2 As New HashSet(Of Integer) From {2, 3}

		' Checks if set2 is a subset of set1
		Dim isSubset As Boolean = set2.IsSubsetOf(set1)

		' Checks if set1 is a superset of set2
		Dim isSuperset As Boolean = set1.IsSupersetOf(set2)

		Console.WriteLine($"Is set2 a subset of set1: {isSubset}")
		Console.WriteLine($"Is set1 a superset of set2: {isSuperset}")
	End Sub
End Class

using System;
using System.Collections.Generic;

class Program
{
    static void Main()
    {
        HashSet<int> set1 = new HashSet<int> { 1, 2, 3 };
        HashSet<int> set2 = new HashSet<int> { 3, 4, 5 };

        // Keeps elements that are in set1 or set2 but not in both
        set1.SymmetricExceptWith(set2);

        Console.WriteLine("Symmetric difference of set1 and set2:");
        foreach (var item in set1)
        {
            Console.WriteLine(item);
        }
    }
}

Imports System
Imports System.Collections.Generic

Friend Class Program
	Shared Sub Main()
		Dim set1 As New HashSet(Of Integer) From {1, 2, 3}
		Dim set2 As New HashSet(Of Integer) From {3, 4, 5}

		' Keeps elements that are in set1 or set2 but not in both
		set1.SymmetricExceptWith(set2)

		Console.WriteLine("Symmetric difference of set1 and set2:")
		For Each item In set1
			Console.WriteLine(item)
		Next item
	End Sub
End Class

using IronPdf;
using System;
using System.Collections.Generic;

class PdfGenerator
{
    static void Main()
    {
        // Sample user names with duplicates
        string[] userNames = { "Alice", "Bob", "Charlie", "Bob", "David", "Alice" };

        // Using HashSet to ensure unique user names
        HashSet<string> uniqueUserNames = new HashSet<string>(userNames);

        // Generating PDF with unique user names
        GeneratePdf(uniqueUserNames);
    }

    static void GeneratePdf(HashSet<string> uniqueUserNames)
    {
        // Create a new PDF document using IronPDF
        HtmlToPdf renderer = new HtmlToPdf();

        // Render a PDF from an HTML document consisting of unique user names
        var pdf = renderer.RenderHtmlAsPdf(BuildHtmlDocument(uniqueUserNames));

        // Save the PDF to a file
        string pdfFilePath = "UniqueUserNames.pdf";
        pdf.SaveAs(pdfFilePath);

        // Display a message with the file path
        Console.WriteLine($"PDF generated successfully. File saved at: {pdfFilePath}");
    }

    static string BuildHtmlDocument(HashSet<string> uniqueUserNames)
    {
        // Build an HTML document with unique user names
        string htmlDocument = "<html><body><ul>";
        foreach (var userName in uniqueUserNames)
        {
            htmlDocument += $"<li>{userName}</li>";
        }
        htmlDocument += "</ul></body></html>";
        return htmlDocument;
    }
}

Imports IronPdf
Imports System
Imports System.Collections.Generic

Friend Class PdfGenerator
	Shared Sub Main()
		' Sample user names with duplicates
		Dim userNames() As String = { "Alice", "Bob", "Charlie", "Bob", "David", "Alice" }

		' Using HashSet to ensure unique user names
		Dim uniqueUserNames As New HashSet(Of String)(userNames)

		' Generating PDF with unique user names
		GeneratePdf(uniqueUserNames)
	End Sub

	Private Shared Sub GeneratePdf(ByVal uniqueUserNames As HashSet(Of String))
		' Create a new PDF document using IronPDF
		Dim renderer As New HtmlToPdf()

		' Render a PDF from an HTML document consisting of unique user names
		Dim pdf = renderer.RenderHtmlAsPdf(BuildHtmlDocument(uniqueUserNames))

		' Save the PDF to a file
		Dim pdfFilePath As String = "UniqueUserNames.pdf"
		pdf.SaveAs(pdfFilePath)

		' Display a message with the file path
		Console.WriteLine($"PDF generated successfully. File saved at: {pdfFilePath}")
	End Sub

	Private Shared Function BuildHtmlDocument(ByVal uniqueUserNames As HashSet(Of String)) As String
		' Build an HTML document with unique user names
		Dim htmlDocument As String = "<html><body><ul>"
		For Each userName In uniqueUserNames
			htmlDocument &= $"<li>{userName}</li>"
		Next userName
		htmlDocument &= "</ul></body></html>"
		Return htmlDocument
	End Function
End Class