C#藉由iTextSharp來達成多個PDF合併處裡

C#藉由iTextSharp來達成多個PDF合併處裡_三異常排除

- 6月 01, 2021

PDF合併的功能程式

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using iTextSharp.text;
using iTextSharp.text.pdf;
namespace EPOOPS_Scheduler.App_Code.Public.Utility
{
    class PdfHelper
    {
        #region "private field"
        private Font _font;
        private Rectangle _rect;
        private Document _document;
        private BaseFont _baseFont;
        #endregion

        public PdfHelper()
        {

        }

        public PdfHelper(string type)
        {
            SetPageSize(type);
            _document = new Document(_rect);
        }

        public void Open(Stream stream)
        {
            PdfWriter.GetInstance(_document, stream);
            _document.Open();
        }

        public void Close()
        {
            _document.Close();
        }

        public void SetPageSize(string type)
        {
            switch (type.Trim())
            {
                case "A4":
                    _rect = PageSize.A4;
                    break;
                case "A8":
                    _rect = PageSize.A8;
                    break;
            }
        }

        public void SetFont(float size)
        {
            _font = new Font(_baseFont, size);
        }

        /// <summary>
        /// 合併多個pdf檔案
        /// </summary>
        /// <param name="lsPdfFile">目標要合併的pdf文件</param>
        /// <param name="mergedFile">最終存出合併pdf</param>
        /// <param name="isVertical">是否要直印，預設為直印</param>
        public static void MergePdfFiles(List<string> lsPdfFile, string mergedFile, bool isVertical = true)
        {
            PdfReader reader;
            Document document = new Document();
            if (!isVertical)
            {
                document = new Document(iTextSharp.text.PageSize.A4.Rotate());
            }

            PdfWriter writer = null;

            writer = PdfWriter.GetInstance(document, new FileStream(mergedFile, FileMode.Create));

            document.Open();

            PdfContentByte cb = writer.DirectContent;
            PdfImportedPage newPage;

            for (int i = 0; i < lsPdfFile.Count; i++)
            {
                if (lsPdfFile[i] != null && lsPdfFile[i] != string.Empty)
                {
                    reader = new PdfReader(lsPdfFile[i]);
                    int iPageNum = reader.NumberOfPages;

                    for (int j = 1; j <= iPageNum; j++)
                    {
                        document.NewPage();
                        newPage = writer.GetImportedPage(reader, j);
                        //reader.Close();
                        //reader.Dispose();
                        cb.AddTemplate(newPage, 0, 0);
                    }
                    writer.FreeReader(reader);
                    reader.Close();
                    reader.Dispose();
                }
            }

            document.Close();
        }

    }
}