How to use C# to Combine Multiple PDF Files

using System;

using System.Collections.Generic;

using System.IO;

using System.ServiceModel;

using System.Windows.Forms;

using Simple_PDF_Converter_Sample.ServiceReference1;

namespace Simple_PDF_Converter_Sample

{

    public partial class Form1 : Form

    {

        // ** The URL where the Web Service is located. Amend host name if needed.

        string SERVICE_URL = "https://localhost:41734/Muhimbi.DocumentConverter.WebService/";

        public Form1()

        {

            InitializeComponent();

        }

        private void button1_Click(object sender, EventArgs e)

        {

            DocumentConverterServiceClient client = null;

            try

            {

                // ** Options and all settings for batch conversion

                ProcessingOptions processingOptions = new ProcessingOptions();

                // ** Specify the minimum level of merge settings

                MergeSettings mergeSettings = new MergeSettings();

                mergeSettings.BreakOnError = false;

                mergeSettings.Watermarks = CreateWatermarks();

                processingOptions.MergeSettings = mergeSettings;

                // ** Get all files in the folder

                string sourceFolder = textBox1.Text;

                string[] sourceFileNames = Directory.GetFiles(sourceFolder);

                // ** Iterate over all files and create a list of SourceFile Objects

                List<SourceFile> sourceFiles = new List<SourceFile>();

                foreach (string sourceFileName in sourceFileNames)

                {

                    // ** Read the contents of the file

                    byte[] sourceFileContent = File.ReadAllBytes(sourceFileName);

                    // ** Set the absolute minimum open options

                    OpenOptions openOptions = new OpenOptions();

                    openOptions.OriginalFileName = Path.GetFileName(sourceFileName);

                    openOptions.FileExtension = Path.GetExtension(sourceFileName);

                    // ** Set the absolute minimum conversion settings.

                    ConversionSettings conversionSettings = new ConversionSettings();

                    conversionSettings.Fidelity = ConversionFidelities.Full;

                    conversionSettings.Quality = ConversionQuality.OptimizeForPrint;

                    // ** Create merge settings for each file and set the name for the PDF bookmark

                    FileMergeSettings fileMergeSettings = new FileMergeSettings();

                    fileMergeSettings.TopLevelBookmark = openOptions.OriginalFileName;

                    // ** Create a source file object and add it to the list

                    SourceFile sourceFile = new SourceFile();

                    sourceFile.OpenOptions = openOptions;

                    sourceFile.ConversionSettings = conversionSettings;

                    sourceFile.MergeSettings = fileMergeSettings;

                    sourceFile.File = sourceFileContent;

                    sourceFiles.Add(sourceFile);

                }

                // ** Assign source files

                processingOptions.SourceFiles = sourceFiles.ToArray();

                // ** Open the service and configure the bindings

                client = OpenService(SERVICE_URL);

                // ** Carry out the merge process

                BatchResults results = client.ProcessBatch(processingOptions);

                // ** Read the results of the merged file.

                byte[] mergedFile = results.Results[0].File;

                // ** Write the converted file back using the name of the folder

                string folderName = new DirectoryInfo(sourceFolder).Name;

                DirectoryInfo parentFolder = Directory.GetParent(sourceFolder);

                string destinationFileName = Path.Combine(parentFolder.FullName, folderName + ".pdf");

                using (FileStream fs = File.Create(destinationFileName))

                {

                    fs.Write(mergedFile, 0, mergedFile.Length);

                    fs.Close();

                }

                MessageBox.Show("Contents of directory merged to " + destinationFileName);

            }

            catch (FaultException<WebServiceFaultException> ex)

            {

                MessageBox.Show("FaultException occurred: ExceptionType: " +

                                ex.Detail.ExceptionType.ToString());

            }

            catch (Exception ex)

            {

                MessageBox.Show(ex.ToString());

            }

            finally

            {

                CloseService(client);

            }

        }

        /// <summary>

        /// Configure the Bindings, endpoints and open the service using the specified address.

        /// </summary>

        /// <returns>An instance of the Web Service.</returns>

        public static DocumentConverterServiceClient OpenService(string address)

        {

            DocumentConverterServiceClient client = null;

            try

            {

                BasicHttpBinding binding = new BasicHttpBinding();

                // ** Use standard Windows Security.

                binding.Security.Mode = BasicHttpSecurityMode.TransportCredentialOnly;

                binding.Security.Transport.ClientCredentialType =

                                                            HttpClientCredentialType.Windows;

                // ** Increase the Timeout to deal with (very) long running requests.

                binding.SendTimeout = TimeSpan.FromMinutes(30);

                binding.ReceiveTimeout = TimeSpan.FromMinutes(30);

                // ** Set the maximum document size to 40MB

                binding.MaxReceivedMessageSize = 50 * 1024 * 1024;

                binding.ReaderQuotas.MaxArrayLength = 50 * 1024 * 1024;

                binding.ReaderQuotas.MaxStringContentLength = 50 * 1024 * 1024;

                // ** Specify an identity (any identity) in order to get it past .net3.5 sp1

                EndpointIdentity epi = EndpointIdentity.CreateUpnIdentity("unknown");

                EndpointAddress epa = new EndpointAddress(new Uri(address), epi);

                client = new DocumentConverterServiceClient(binding, epa);

                client.Open();

                return client;


            }

            catch (Exception)

            {
            CloseService(client);

                throw;

            }

        }

        /// <summary>

        /// Check if the client is open and then close it.

        /// </summary>

        /// <param name="client">The client to close</param>

        public static void CloseService(DocumentConverterServiceClient client)

        {

            if (client != null && client.State == CommunicationState.Opened)

                client.Close();

        }

        /// <summary>

        /// This method creates watermarks for applying page numbers

        /// </summary>

        /// <returns>Array of watermarks</returns>

        private Watermark[] CreateWatermarks()

        {

            // ** Create watermark container

            Watermark pageWatermark = new Watermark();

            // ** Set positioning to the lower right of the page

            pageWatermark.HPosition = HPosition.Right;

            pageWatermark.VPosition = VPosition.Bottom;

            // ** Set size

            pageWatermark.Width = "200";

            pageWatermark.Height = "20";

            // ** Create text object for the page numbering

            Text oddPageText = new Text();

            // ** No need to position the element in the watermark container

            oddPageText.Width = "200";

            oddPageText.Height = "20";

            // ** set content including field codes

            oddPageText.Content = "Page {PAGE} of {NUMPAGES}";

            // ** set font properties

            oddPageText.FillColor = "#ffff0000";

            oddPageText.FontFamilyName = "Verdana";

            oddPageText.FontSize = "10";

            oddPageText.FontStyle = FontStyle.Regular;


            //* set text alignment

            oddPageText.HAlign = HAlign.Right;

            oddPageText.VAlign = VAlign.Top;

            //** create array of watermark elements

            Element[] pageWatermarkElements = new Element[] { oddPageText };

            //** set elements of watermark

            pageWatermark.Elements = pageWatermarkElements;

            //* return array of watermarks

            return new Watermark[] { pageWatermark };

        }

    }

}