PDF-Merge/MergePDFs.cs

namespace PDF_Merge
{
    using System;
    using System.Configuration;
    using System.IO;
    using System.Linq;
    using System.Windows.Forms;
    using PdfSharp.Pdf;
    using PdfSharp.Pdf.IO;
    class MergePDFs
    {
        public static void MergePdfFiles(string[] filePaths, string outputPath)
        {
            
            using (var output = new PdfDocument())
            {
                if (ConfigurationManager.AppSettings["overwrite"] == true.ToString())
                {
                    if (File.Exists(outputPath))
                    {
                        try
                        {

                            System.IO.File.Delete(outputPath);
                        }
                        catch
                        {
                            MessageBox.Show("Error deleting the old PDF.", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
                        }
                    }
                }
                foreach (var file in filePaths)
                {
                    try
                    {
                        using (var input = PdfReader.Open(file, PdfDocumentOpenMode.Import))
                        {
                            for (int i = 0; i < input.Pages.Count; i++)
                            {
                                output.AddPage(input.Pages[i]);
                            }
                        }
                    } catch { }
                }
                
                try
                {
                    
                    output.Save(outputPath);
                    if (File.Exists(outputPath))
                    {
                        MessageBox.Show("PDF saved.", "Info", MessageBoxButtons.OK, MessageBoxIcon.Information);
                    }
                }
                catch 
                {
                    MessageBox.Show("PDF cannot be empty. There were no documents processed.", "Error" ,MessageBoxButtons.OK, MessageBoxIcon.Error);
                }
            }
        }
        public static string[] CollectPdfFiles()
        {
            string dirPath = ConfigurationManager.AppSettings["PDF-Path"];
            Console.WriteLine(dirPath);
            string[] pdfFiles = Directory.EnumerateFiles(dirPath, "*.pdf").ToArray();
            Array.Sort(pdfFiles);
            if (pdfFiles.Length != 0)
            {
                foreach (string file in pdfFiles)
                {
                    Console.WriteLine(file);
                }
            }
            else
            {
                MessageBox.Show("No PDFs were found in the configured directory.", "Info", MessageBoxButtons.OK, MessageBoxIcon.Information);
            }
            return pdfFiles;
        }

        public static string GetDate()
        {
            DateTime date = DateTime.Now;
            string dateFormat = ConfigurationManager.AppSettings["dateFormat"];
            return date.ToString(dateFormat);
        }
    }
   
}