PDF文件合并

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using iTextSharp.text;
using iTextSharp.text.pdf;
using System.IO;

/// <summary>
///PDFMergeManager 的摘要说明
///pdf文件合并处理类
/// </summary>
public class PDFMergeManager
{
    private PdfWriter pw;
    private PdfReader reader;
    private Document document;
    private PdfContentByte cb;
    private PdfImportedPage newPage;
    /// <summary>
    /// 通过输出文件来构建合并管理，合并到新增文件中,合并完成后调用FinishedMerge方法
    /// </summary>
    /// <param name="sOutFiles"></param>
    public PDFMergeManager(string sOutFiles)
    {
        document = new Document(PageSize.A4);
        if (File.Exists(sOutFiles))
        {
            document = null;
            throw new IOException("用户取消操作");
        }
        pw = PdfWriter.GetInstance(document, new FileStream(sOutFiles, FileMode.Create));
        document.Open();
        cb = pw.DirectContent;
    }
    /// <summary>
    /// 通过文件流来合并文件，合并到当前的可写流中，合并完成后调用FinishedMerge方法
    /// </summary>
    /// <param name="sm"></param>
    public PDFMergeManager(Stream sm)
    {
        document = new Document();
        pw = PdfWriter.GetInstance(document, sm);
        document.Open();
        cb = pw.DirectContent;
    }
    /// <summary>
    /// 合并文件
    /// </summary>
    /// <param name="sFiles">需要合并的文件路径名称</param>
    /// <returns></returns>
    public bool MergeFile(string sFiles)
    {
        reader = new PdfReader(sFiles);
        {
            int iPageNum = reader.NumberOfPages;
            for (int j = 1; j <= iPageNum; j++)
            {

                newPage = pw.GetImportedPage(reader, j);
                Rectangle r = reader.GetPageSize(j);
                document.SetPageSize(r);
                document.NewPage();
                cb.AddTemplate(newPage, 0, 0);
            }

        }
        reader.Close();
        return true;
    }
    /// <summary>
    /// 通过字节数据合并文件
    /// </summary>
    /// <param name="pdfIn">PDF字节数据</param>
    /// <returns></returns>
    public bool MergeFile(byte[] pdfIn)
    {
        reader = new PdfReader(pdfIn);
        {
            int iPageNum = reader.NumberOfPages;
            for (int j = 1; j <= iPageNum; j++)
            {
                newPage = pw.GetImportedPage(reader, j);
                Rectangle r = reader.GetPageSize(j);
                document.SetPageSize(r);
                document.NewPage();
                cb.AddTemplate(newPage, 0, 0);
            }
        }
        reader.Close();
        return true;
    }
    /// <summary>
    /// 通过PDF文件流合并文件
    /// </summary>
    /// <param name="pdfStream">PDF文件流</param>
    /// <returns></returns>
    public bool MergeFile(Stream pdfStream)
    {
        reader = new PdfReader(pdfStream);
        {
            int iPageNum = reader.NumberOfPages;
            for (int j = 1; j <= iPageNum; j++)
            {
                newPage = pw.GetImportedPage(reader, j);
                Rectangle r = reader.GetPageSize(j);
                document.SetPageSize(r);
                document.NewPage();
                cb.AddTemplate(newPage, 0, 0);
            }
        }
        reader.Close();
        return true;
    }
    /// <summary>
    /// 通过网络地址来合并文件
    /// </summary>
    /// <param name="pdfUrl">需要合并的PDF的网络路径</param>
    /// <returns></returns>
    public bool MergeFile(Uri pdfUrl)
    {
        reader = new PdfReader(pdfUrl);
        {
            int iPageNum = reader.NumberOfPages;
            for (int j = 1; j <= iPageNum; j++)
            {
                newPage = pw.GetImportedPage(reader, j);
                Rectangle r = reader.GetPageSize(j);
                document.SetPageSize(r);
                document.NewPage();
                cb.AddTemplate(newPage, 0, 0);
            }
        }
        reader.Close();
        return true;
    }
    /// <summary>
    /// 完成合并
    /// </summary>
    public void FinishedMerge()
    {
        try
        {
            if (reader != null)
            {
                reader.Close();
            }
            if (pw != null)
            {
                pw.Flush();
                pw.Close();
            }
            if (document.IsOpen())
            {
                document.Close();
            }
        }
        catch
        {
        }
    }
}