C# Interlocked（它如何對開發者起作用）

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

class Program
{
    static int pageCount = 0;
    static readonly object lockObject = new object(); // Object for locking

    static void Main()
    {
        var threads = new Thread[5];
        List<PdfDocument> pdfList = new List<PdfDocument>();

        // Create threads for parallel PDF generation
        for (int i = 0; i < threads.Length; i++)
        {
            threads[i] = new Thread(() => GeneratePdf(pdfList));
            threads[i].Start();
        }

        // Wait for all threads to complete
        foreach (var thread in threads)
        {
            thread.Join();
        }

        // Merge all the generated PDFs
        PdfDocument finalPdf = pdfList[0]; // Start with the first document

        // Merge remaining PDFs into finalPdf
        for (int i = 1; i < pdfList.Count; i++)
        {
            finalPdf = PdfDocument.Merge(finalPdf, pdfList[i]);
        }

        // Save the merged PDF
        finalPdf.SaveAs("MergedGeneratedPDF.pdf");
        Console.WriteLine("All PDFs merged and saved successfully.");
    }

    static void GeneratePdf(List<PdfDocument> pdfList)
    {
        // Use ChromePdfRenderer instead of HtmlToPdf
        ChromePdfRenderer renderer = new ChromePdfRenderer();

        // Use Interlocked to ensure unique page number per thread and using a "ref object" to reference the pageCount object 
        int pageNum = Interlocked.Increment(ref pageCount);

        // Generate a PDF page using ChromePdfRenderer
        var pdfPage = renderer.RenderHtmlAsPdf($"Page {pageNum} generated by thread {Thread.CurrentThread.ManagedThreadId}");

        // Add generated PDF page to the list (thread-safe)
        lock (lockObject) // Ensure thread-safety when adding to shared list
        {
            pdfList.Add(pdfPage);
        }

        string fileName = $"GeneratedPDF_{pageNum}.pdf";
        pdfPage.SaveAs(fileName);
        Console.WriteLine($"Thread {Thread.CurrentThread.ManagedThreadId} generated: {fileName}");
    }
}

Imports IronPdf
Imports System
Imports System.Threading
Imports System.Collections.Generic

Friend Class Program
	Private Shared pageCount As Integer = 0
	Private Shared ReadOnly lockObject As New Object() ' Object for locking

	Shared Sub Main()
		Dim threads = New Thread(4){}
		Dim pdfList As New List(Of PdfDocument)()

		' Create threads for parallel PDF generation
		For i As Integer = 0 To threads.Length - 1
			threads(i) = New Thread(Sub() GeneratePdf(pdfList))
			threads(i).Start()
		Next i

		' Wait for all threads to complete
		For Each thread In threads
			thread.Join()
		Next thread

		' Merge all the generated PDFs
		Dim finalPdf As PdfDocument = pdfList(0) ' Start with the first document

		' Merge remaining PDFs into finalPdf
		For i As Integer = 1 To pdfList.Count - 1
			finalPdf = PdfDocument.Merge(finalPdf, pdfList(i))
		Next i

		' Save the merged PDF
		finalPdf.SaveAs("MergedGeneratedPDF.pdf")
		Console.WriteLine("All PDFs merged and saved successfully.")
	End Sub

	Private Shared Sub GeneratePdf(ByVal pdfList As List(Of PdfDocument))
		' Use ChromePdfRenderer instead of HtmlToPdf
		Dim renderer As New ChromePdfRenderer()

		' Use Interlocked to ensure unique page number per thread and using a "ref object" to reference the pageCount object 
		Dim pageNum As Integer = Interlocked.Increment(pageCount)

		' Generate a PDF page using ChromePdfRenderer
		Dim pdfPage = renderer.RenderHtmlAsPdf($"Page {pageNum} generated by thread {Thread.CurrentThread.ManagedThreadId}")

		' Add generated PDF page to the list (thread-safe)
		SyncLock lockObject ' Ensure thread-safety when adding to shared list
			pdfList.Add(pdfPage)
		End SyncLock

		Dim fileName As String = $"GeneratedPDF_{pageNum}.pdf"
		pdfPage.SaveAs(fileName)
		Console.WriteLine($"Thread {Thread.CurrentThread.ManagedThreadId} generated: {fileName}")
	End Sub
End Class

try
{
    finalPdf.SaveAs(fileName);
}
catch (Exception ex)
{
    Console.WriteLine($"Error generating PDF: {ex.Message}");
}

Try
	finalPdf.SaveAs(fileName)
Catch ex As Exception
	Console.WriteLine($"Error generating PDF: {ex.Message}")
End Try