C# ObservableCollection（對開發者來說是如何工作的）

using IronPdf;
using System.Collections.Generic;
using System;
namespace PdfAutomation
{
    class Program
    {
        static void Main(string[] args)
        {
            // Apply your IronPDF License Key here to remove watermarks
            License.LicenseKey = "YOUR_IRONPDF_LICENSE_KEY";
            Console.WriteLine("Starting PDF Merge Process...");
            try
            {
                // Step 1: Define the paths of the files you wish to merge.
                // These can be absolute paths or relative to the project directory.
                var pdfFilesToMerge = new List<string>
                {
                    @"C:\Documents\Cover_Letter.pdf",
                    @"C:\Documents\Financial_Data.pdf",
                    @"C:\Documents\Standard_Terms.pdf"
                };
                // Step 2: Use the static PdfDocument.Merge method.
                // This method takes an IEnumerable of file paths or an IEnumerable of PdfDocument objects.
                // Passing paths directly is generally more memory efficient for simple concatenations.
                Console.WriteLine("Stitching documents together...");
                PdfDocument mergedDocument = PdfDocument.Merge(pdfFilesToMerge);
                // Step 3: Define the output path and save the result.
                string outputPath = @"C:\Documents\Final_Client_Package.pdf";
                mergedDocument.SaveAs(outputPath);
                // Step 4: Always explicitly dispose of the PdfDocument object to free up system memory immediately.
                mergedDocument.Dispose();
                Console.WriteLine($"Success! Merged document saved to: {outputPath}");
            }
            catch (Exception ex)
            {
                // Robust error handling is critical in production applications.
                // This will catch issues like "File in use by another process" or "File not found".
                Console.WriteLine($"An error occurred during the merge process: {ex.Message}");
            }
        }
    }
}

Imports IronPdf
Imports System.Collections.Generic
Imports System

Namespace PdfAutomation
    Class Program
        Shared Sub Main(ByVal args As String())
            ' Apply your IronPDF License Key here to remove watermarks
            License.LicenseKey = "YOUR_IRONPDF_LICENSE_KEY"
            Console.WriteLine("Starting PDF Merge Process...")
            Try
                ' Step 1: Define the paths of the files you wish to merge.
                ' These can be absolute paths or relative to the project directory.
                Dim pdfFilesToMerge As New List(Of String) From {
                    "C:\Documents\Cover_Letter.pdf",
                    "C:\Documents\Financial_Data.pdf",
                    "C:\Documents\Standard_Terms.pdf"
                }
                ' Step 2: Use the static PdfDocument.Merge method.
                ' This method takes an IEnumerable of file paths or an IEnumerable of PdfDocument objects.
                ' Passing paths directly is generally more memory efficient for simple concatenations.
                Console.WriteLine("Stitching documents together...")
                Dim mergedDocument As PdfDocument = PdfDocument.Merge(pdfFilesToMerge)
                ' Step 3: Define the output path and save the result.
                Dim outputPath As String = "C:\Documents\Final_Client_Package.pdf"
                mergedDocument.SaveAs(outputPath)
                ' Step 4: Always explicitly dispose of the PdfDocument object to free up system memory immediately.
                mergedDocument.Dispose()
                Console.WriteLine($"Success! Merged document saved to: {outputPath}")
            Catch ex As Exception
                ' Robust error handling is critical in production applications.
                ' This will catch issues like "File in use by another process" or "File not found".
                Console.WriteLine($"An error occurred during the merge process: {ex.Message}")
            End Try
        End Sub
    End Class
End Namespace

using IronPdf;
using System.Collections.Generic;
public byte[] GenerateMergedReport()
{
    // Initialize the HTML to PDF renderer
    var renderer = new ChromePdfRenderer();
    // Generate PDF objects directly from HTML strings in memory
    PdfDocument coverPage = renderer.RenderHtmlAsPdf("<h1>Annual Report</h1><p>Confidential Internal Document</p>");
    PdfDocument dataChart = renderer.RenderUrlAsPdf("https://internal.dashboard/report/12345");
    // Add existing PdfDocument objects to a list
    var documents = new List<PdfDocument> { coverPage, dataChart };
    // Merge the in-memory objects
    PdfDocument finalReport = PdfDocument.Merge(documents);
    // Export the merged document as a Byte Array
    byte[] pdfBytes = finalReport.BinaryData;
    // Dispose of all objects to prevent memory leaks in the web server
    coverPage.Dispose();
    dataChart.Dispose();
    finalReport.Dispose();
    // This byte array can now be returned as a File() result in an MVC controller
    return pdfBytes;
}

Imports IronPdf
Imports System.Collections.Generic

Public Function GenerateMergedReport() As Byte()
    ' Initialize the HTML to PDF renderer
    Dim renderer As New ChromePdfRenderer()
    ' Generate PDF objects directly from HTML strings in memory
    Dim coverPage As PdfDocument = renderer.RenderHtmlAsPdf("<h1>Annual Report</h1><p>Confidential Internal Document</p>")
    Dim dataChart As PdfDocument = renderer.RenderUrlAsPdf("https://internal.dashboard/report/12345")
    ' Add existing PdfDocument objects to a list
    Dim documents As New List(Of PdfDocument) From {coverPage, dataChart}
    ' Merge the in-memory objects
    Dim finalReport As PdfDocument = PdfDocument.Merge(documents)
    ' Export the merged document as a Byte Array
    Dim pdfBytes As Byte() = finalReport.BinaryData
    ' Dispose of all objects to prevent memory leaks in the web server
    coverPage.Dispose()
    dataChart.Dispose()
    finalReport.Dispose()
    ' This byte array can now be returned as a File() result in an MVC controller
    Return pdfBytes
End Function