我正在做一个项目，我需要在显示之前编辑 pdf
我需要
- 添加水印
- 编辑权限（锁定以避免“复制/粘贴”和“另存为”）
- 编辑查看器首选项
我做到了......并且工作正常，除了一件事，原始文件中的链接在新文件中不起作用......知道吗？
注意：实际上，这是我的代码（我使用的是 itextsharp）
private void loadPdf()
{
if (Request.QueryString.HasKeys())
{
if (Request.QueryString.GetKey(0) == "thepath" && Request.QueryString.GetKey(1) == "isprintable" && Request.QueryString.GetKey(2) == "type")
{
#region kuak
Document doc = new Document();
PdfReader pdfReader = new PdfReader(Request.QueryString["thepath"]);
using (MemoryStream memoryStream = new MemoryStream())
{
PdfWriter pdfWriter = PdfWriter.GetInstance(doc, memoryStream);
pdfWriter.ViewerPreferences = PdfWriter.PageModeUseOutlines;
//pdfWriter.ViewerPreferences = PdfWriter.PageLayoutTwoColumnLeft; /// Despliega el docuemnto en pares de hojas
pdfWriter.ViewerPreferences = PdfWriter.PageLayoutOneColumn;
pdfWriter.ViewerPreferences = PdfWriter.HideToolbar;
//pdfWriter.ViewerPreferences = PdfWriter.HideWindowUI; /// quita los scrollbars y el panel de la derecha qur contiene los bookmarks y las buskedas dentro del pdf
if (Request.QueryString["isprintable"] == "n")
{
pdfWriter.ViewerPreferences = PdfWriter.HideMenubar;
System.Text.UTF8Encoding encoding = new System.Text.UTF8Encoding();
pdfWriter.SetEncryption(null, encoding.GetBytes("mYpAssss"), 0, PdfWriter.STRENGTH40BITS);
}
doc.Open();
PdfContentByte pdfContentByte = pdfWriter.DirectContent;
doc.AddDocListener(pdfWriter);
for (int page = 1; page <= pdfReader.NumberOfPages; page++)
{
//doc.SetPageSize(pdfReader.GetPageSize(page));
doc.SetPageSize(pdfReader.GetPageSizeWithRotation(page));
doc.NewPage();
PdfImportedPage pdfImportedPage = pdfWriter.GetImportedPage(pdfReader, page);
int rot = pdfReader.GetPageRotation(page);
if (rot == 90 || rot == 270)
pdfContentByte.AddTemplate(pdfImportedPage, 0, -1.0F, 1.0F, 0, 0, pdfReader.GetPageSizeWithRotation(page).Height);
else
pdfContentByte.AddTemplate(pdfImportedPage, 1.0F, 0, 0, 1.0F, 0, 0);
string theId = findId();
if (isWatermarkNeeded(theId))
{
#region ADD TEXT WATERMARK
//pdfContentByte.BeginText();
//iTextSharp.text.Rectangle pageSize = pdfReader.GetPageSizeWithRotation(page);
//BaseFont baseFont = BaseFont.CreateFont(BaseFont.HELVETICA_BOLD, System.Text.Encoding.ASCII.EncodingName, false);
//pdfContentByte.SetFontAndSize(baseFont, 200);
//BaseColor baseColor = new BaseColor(255, 0, 0, 20);
//pdfContentByte.SetColorFill(baseColor);
//float textAngle = (float)GetHypotenuseAngleInDegreesFrom(pageSize.Height, pageSize.Width);
//pdfContentByte.ShowTextAligned(PdfContentByte.ALIGN_CENTER, "DRAFT", 350, pageSize.Height / 2, textAngle);
//pdfContentByte.EndText();
#endregion
#region ADD IMAGE WATERMARK
string fechaExp = "Este documento vence: " + GetExpirationDate(theId).ToShortDateString();
pdfContentByte.BeginText();
//iTextSharp.text.Image img = iTextSharp.text.Image.GetInstance(Server.MapPath("~/images/watermark3.png"));
iTextSharp.text.Image img = iTextSharp.text.Image.GetInstance(ImageCheck.CreatePicture(@"C:\Users\myUser\Desktop\watermark.png", fechaExp).ToArray());
img.SetAbsolutePosition(0, 0);
pdfContentByte.AddImage(img);
pdfContentByte.EndText();
#endregion
}
}
pdfReader.Close();
doc.Close();
byte[] content = memoryStream.ToArray();
Response.ContentType = "application/pdf";
Response.AddHeader("content-length", content.Length.ToString());
Response.BinaryWrite(content);
}
#endregion
}
else
{
//hay querystring pro no corresponden con los que se necesita
}
}
else
{
//no se enviaron los querystring
}
}