PdfiumViewer组件扩展(Pdfium.Net.Free)--快速入门

项目地址：

Pdfium.Net：https://github.com/1000374/Pdfium.Net.Free

PdfiumViewer：https://github.com/1000374/PdfiumViewer

Pdfium.Net.Free 支持

• .NETFramework 4.0

• .NETFramework 4.5

• .NETStandard 2.0

• .Net8.0

可以和PdfiumViewer.Free共同使用预览、编辑pdf，也可以直接引用Pdfium.Net.Free 操作pdf，Pdfium.Net.Free封装了现有Pdfium的函数，实现了部分操作pdf的功能，部分功能等待后续~~

打开PDF：

 var pathPdf = "./Pdfium.NetTests/resources/about_blank.pdf";
 using (var doc = PdfDocument.Load(new MemoryStream(File.ReadAllBytes(pathPdf))))
     Assert.IsTrue(!doc.IsNull);

 

创建PDF 添加页面：

   using (var doc = PdfDocument.CreateNew())
   {
       doc.Pages.Add(612, 792);
       Assert.AreEqual(612, doc.Pages[0].Width);
   }

添加字符集

//添加通过字符集
 using (var doc = PdfDocument.CreateNew())
 {
     var fontPath = @"c:\Windows\fonts\simhei.ttf";
     byte[] fontData = File.ReadAllBytes(fontPath);
     var font = doc.TextLoadFont(fontData, fontData.Length, PdfFontTypes.TrueType, true);
 }
//添加标准字符集
    using (var doc = PdfDocument.CreateNew())
    {
        var font = doc.TextLoadStandardFont(StandardPDFFonts.Arial);
    }

添加文字：

//添加文字 指定字库 字库内嵌
 using (var doc = PdfDocument.CreateNew())
 {
     var fontPath = @"c:\Windows\fonts\simhei.ttf";
     doc.LoadFont(fontPath);
     var cSharpString = "!you ok 这是第一句。 这是第二行。a you ok 你好 abcdefghijklmnopqrstuvwxyz1234567890-*/+~`@#$%^&*(){}[];:'|?,，。.！!";
     var page = doc.Pages.Add(612, 792);
     page.AddString(cSharpString, 10, 50, 12, Color.Black);
     doc.Save("./Pdfium.NetTests/AddString2.pdf");
 }

//使用标准字库 英语 中文乱码
 using (var doc = PdfDocument.CreateNew())
 {
     var cSharpString = "!you ok 这是第一句。 这是第二行。a you ok";
     var page = doc.Pages.Add(612, 792);
     page.AddString(cSharpString, 10, 50, 12, Color.Black, StandardPDFFonts.TimesNewRoman);
     doc.Save("./Pdfium.NetTests/AddString1.pdf");
 }
//字符子集 根据写入问题拆分字符子集并嵌入pdf内
 using (var doc = PdfDocument.CreateNew())
 {
     var fontPath = @"c:\Windows\fonts\simhei.ttf";

     var cSharpString = "!you ok 这是第一句。";
     var cSharpString2 = " 这是第二行。a you ok 你好 abcdefghijklmnopqrstuvwxyz1234567890-*/+~`@#$%^&*(){}[];:'|?,，。.！!";
     doc.LoadFont(fontPath, true, cSharpString + cSharpString2);
     var page = doc.Pages.Add(612, 792);
     page.AddString(cSharpString, 10, 50, 12, Color.Black);

     page.AddString(cSharpString2, 10, 80, 12, Color.Black);
     doc.Save("./Pdfium.NetTests/AddString3.pdf");
 }

获取pdf内部已有字符添加文字：

 var pathPdf = "./Pdfium.NetTests/resources/fontText.pdf";
 using (var doc = PdfDocument.Load(new MemoryStream(File.ReadAllBytes(pathPdf))))
 {
     var font = doc.Pages[0].GetTextObjFont("你", out float size);
     if (!font.IsNull)
     {
         var emb = font.IsEmbedded;
         var cSharpString = "你好啊,abc";
         var page = doc.Pages[0];
         page.AddString(cSharpString, 10, 50, size, Color.Black, font);
         doc.Save("./Pdfium.NetTests/TextObjFont.pdf");
     }
 }

添加水印：

//样式1 实线 
using (var doc = PdfDocument.CreateNew())
 {
     doc.Pages.Add(612, 792);
     var fontPath = @"c:\Windows\fonts\simhei.ttf";
     var cSharpString = "我是水印";
     doc.LoadFont(fontPath, true, cSharpString);

     doc.WaterMark(cSharpString, 20, Color.FromArgb(50, 255, 0, 0), totleHeight: 120);
     doc.Save("./Pdfium.NetTests/WaterMark.pdf");
 }
//样式2 中空
 using (var doc = PdfDocument.CreateNew())
 {
     doc.Pages.Add(612, 792);
     var fontPath = @"c:\Windows\fonts\simhei.ttf";
     doc.LoadFont(fontPath);
     var cSharpString = "我是水印";
     doc.WaterMark(cSharpString, 20, Color.FromArgb(50, 255, 0, 0), totleHeight: 120, render_mode: PdfTextRenderMode.Stroke);
     doc.Save("./Pdfium.NetTests/WaterMark1.pdf");
 }

添加图片：

//添加流  
using (var doc = PdfDocument.CreateNew())
  {
      var imagePath = "./Pdfium.NetTests/resources/mona_lisa.jpg";
      var page = doc.Pages.Add(612, 792);
      var stream = new MemoryStream(File.ReadAllBytes(imagePath));
      page.AddImage(stream, 50, 100);
      doc.Save("./Pdfium.NetTests/AddImage.pdf");
  }
//添加image对象
using (var doc = PdfDocument.CreateNew())
{
   
    var imagePath = "./Pdfium.NetTests/resources/mona_lisa.jpg";
    var image = Image.FromFile(imagePath, true);
    var page = doc.Pages.Add(612, 792);
    page.AddImage(image, 50, 100);
    var page1 = doc.Pages.Add(612, 792);
    page.AddImage(image, 50, 500);
    doc.Save("./Pdfium.NetTests/AddImage1.pdf");
}

pdf每一页转成图片：

//返回image 
 var pathPdf = "./Pdfium.NetTests/resources/annotation_highlight_long_content.pdf";
  using (var doc = PdfDocument.Load(new MemoryStream(File.ReadAllBytes(pathPdf))))
      for (int i = 0; i < doc.PageCount; i++)
      {
          using (var image = doc.Pages[i].Render((int)doc.Pages[i].Width * 4 / 3, (int)doc.Pages[i].Height * 4 / 3, 96, 96, PdfRotation.Rotate0, PdfRenderFlags.Annotations | PdfRenderFlags.CorrectFromDpi))
          {
              Assert.IsNotNull(image);
          }
      }

//通过DOC获取 image
        var pathPdf = "./Pdfium.NetTests/resources/annotation_highlight_long_content.pdf";
        using (var doc = PdfDocument.Load(new MemoryStream(File.ReadAllBytes(pathPdf))))
            for (int i = 0; i < doc.PageCount; i++)
            {
                using (var image = doc.Render(0, 96, 96, true))
                {
                    Assert.IsNotNull(image);
                }
            }
//通过DOC获取 stream
 var pathPdf = "./Pdfium.NetTests/resources/annotation_highlight_long_content.pdf";
 using (var doc = PdfDocument.Load(new MemoryStream(File.ReadAllBytes(pathPdf))))
     for (int i = 0; i < doc.PageCount; i++)
     {
         using (var stream = doc.RenderStream(0, 96, 96, true))
         {
            var image=Image.FromStream(stream);
         }
     }

//自己实现GDI+
 var pathPdf = "./Pdfium.NetTests/resources/annotation_highlight_long_content.pdf";
 using (var doc = PdfDocument.Load(new MemoryStream(File.ReadAllBytes(pathPdf))))
 {
     var page0 = doc.Pages[0];
     Image image = new Bitmap((int)page0.Width, (int)page0.Height);
     var g = Graphics.FromImage(image);
     page0.Render(g, g.DpiX, g.DpiY, new Rectangle(
         AdjustDpi(g.DpiX, 0),
         AdjustDpi(g.DpiY, 0),
         AdjustDpi(g.DpiX, image.Width),
         AdjustDpi(g.DpiY, image.Height)), PdfRotation.Rotate0, PdfRenderFlags.None);
     image.Save("./Pdfium.NetTests/Render.png");
 }
 private static int AdjustDpi(double value, double dpi)
 {
     return (int)(value / 100.0 * dpi);
 }

Ubuntu 请使用如下方式：（可引用SkiaSharp或者直接保存流到图片）

 using (var doc = PdfDocument.Load(new MemoryStream(File.ReadAllBytes(pathPdf))))
     for (int i = 0; i < doc.PageCount; i++)
     {
         var localPath = Path.Combine(path, $"{i}.png");
         using (var stream = doc.RenderStream(i, (int)doc.Pages[i].Width * 4 / 3, (int)doc.Pages[i].Height * 4 / 3, 96 * 2, 96 * 2, PdfRenderFlags.Annotations | PdfRenderFlags.CorrectFromDpi))
         {
             //using (var filestream = new FileStream(localPath,FileMode.OpenOrCreate))
             //{
             //    stream.CopyTo(filestream);
             //}
             var bitmip = SKBitmap.Decode(stream);
             var image = SKImage.FromBitmap(bitmip);
             // 将图片保存为PNG到本地路径
             using (var imageFileStream = new FileStream(localPath, FileMode.Create, FileAccess.Write))
             {
                 image.Encode(SKEncodedImageFormat.Png, 100).SaveTo(imageFileStream);
             }
         }
     }

pdf页局部转成图片：

//返回stream
 var pathPdf = "./Pdfium.NetTests/resources/annotation_highlight_long_content.pdf";
 using (var doc = PdfDocument.Load(new MemoryStream(File.ReadAllBytes(pathPdf))))
     for (int i = 0; i < doc.PageCount; i++)
     {
         using (var image = doc.Pages[i].RenderStream((int)doc.Pages[i].Width * 4 / 3, (int)doc.Pages[i].Height * 4 / 3, 96, 96, PdfRotation.Rotate0, PdfRenderFlags.Annotations | PdfRenderFlags.CorrectFromDpi))
         {
             Assert.IsNotNull(image);
         }
     }

//返回stream
var pathPdf = "./Pdfium.NetTests/resources/annotation_highlight_long_content.pdf";
using (var doc = PdfDocument.Load(new MemoryStream(File.ReadAllBytes(pathPdf))))
    for (int i = 0; i < doc.PageCount; i++)
    {
        using (var image = doc.Pages[i].RenderStream(
            (int)doc.Pages[i].Width,
            (int)doc.Pages[i].Height,
            16, // x of the top/left of clipping rectangle
           283, // y of the top/left point of clipping rectangle
           555, // width of clipping reactangle
           316, // height of clipping reactangle
           0,//DPIx
           0,//DPIy
           PdfRotation.Rotate0, // no rotation
           PdfRenderFlags.None // no render flags
                               ))
        {
          
        }
    }

导出pdf内嵌缩略图：

   var pathPdf = "./Pdfium.NetTests/resources/simple_thumbnail.pdf";
   using (var doc = PdfDocument.Load(new MemoryStream(File.ReadAllBytes(pathPdf))))
       for (int i = 0; i < doc.PageCount; i++)
       {
           var image = doc.Pages[i].RenderThumbnail();
           Assert.IsNotNull(image);
       }

获取PDF内文字：

 var pathPdf = "./Pdfium.NetTests/resources/text_render_mode.pdf";
 using (var doc = PdfDocument.Load(new MemoryStream(File.ReadAllBytes(pathPdf))))
 {
     var text = doc.Pages[0].GetPdfText();
     Assert.AreEqual("fill\r\nstroke\0", text);
 }

获取PDF指定区域的文字：

 //page: 0,x: 235,y: 238,x1: 327,y1: 287 Text: fill
 var pathPdf = "./Pdfium.NetTests/resources/text_render_mode.pdf";
 using (var doc = PdfDocument.Load(new MemoryStream(File.ReadAllBytes(pathPdf))))
 {
     var text = doc.Pages[0].GetBoundedText(235, 238, 327, 287);
     Assert.AreEqual("fill", text);
 }

拆分pdf：

var pathPdf = "./Pdfium.NetTests/resources/viewer_ref.pdf";
using (var doc = PdfDocument.Load(new MemoryStream(File.ReadAllBytes(pathPdf))))
{
for (int i = 0; i < doc.PageCount; i++)
{
var doci = doc.GetPage(i);
Assert.AreEqual(1, doci.PageCount);
}
}

拆分多页：

var pathPdf = "./Pdfium.NetTests/resources/viewer_ref.pdf";
using (var doc = PdfDocument.Load(new MemoryStream(File.ReadAllBytes(pathPdf))))
{
var pages = new int[] { 1, 2, 3 };
var doci = doc.GetPage(pages);
Assert.AreEqual(3, doci.PageCount);
}

合并pdf：

var pathPdf = "./Pdfium.NetTests/resources/viewer_ref.pdf";
using (var doc = PdfDocument.Load(new MemoryStream(File.ReadAllBytes(pathPdf))))
using (var doc1 = PdfDocument.Load(new MemoryStream(File.ReadAllBytes(pathPdf))))
{
doc.MergePage(doc1);
Assert.AreEqual(10, doc.PageCount);
}

插入pdf：

var pathPdf = "./Pdfium.NetTests/resources/viewer_ref.pdf";
var pathPdf1 = "./Pdfium.NetTests/resources/zero_length_stream.pdf";

using (var doc = PdfDocument.Load(new MemoryStream(File.ReadAllBytes(pathPdf))))
using (var doc1 = PdfDocument.Load(new MemoryStream(File.ReadAllBytes(pathPdf1))))
{
doc.ImportPage(doc1, 1);
var w = doc1.Pages[0].Width;
var w1 = doc.Pages[1].Width;
Assert.AreEqual(w, w1);
}

替换pdf：

 var pathPdf = "./Pdfium.NetTests/resources/viewer_ref.pdf";
 var pathPdf1 = "./Pdfium.NetTests/resources/zero_length_stream.pdf";

 using (var doc = PdfDocument.Load(new MemoryStream(File.ReadAllBytes(pathPdf))))
 using (var doc1 = PdfDocument.Load(new MemoryStream(File.ReadAllBytes(pathPdf1))))
 {
     doc.DeletePage(1);
     doc.ImportPage(doc1, 1);
 }

 

多页pdf合并成1页：

  var pathPdf = "./Pdfium.NetTests/resources/rectangles_multi_pages.pdf";
  using (var doc = PdfDocument.Load(new MemoryStream(File.ReadAllBytes(pathPdf))))
  {
      using (var doc1 = doc.ImportNPagesToOne(612 * 2, 792))
          Assert.AreEqual(612 * 2, doc1.Pages[0].Width);
  }

删除页：

  var pathPdf = "./Pdfium.NetTests/resources/viewer_ref.pdf";
  using (var doc = PdfDocument.Load(new MemoryStream(File.ReadAllBytes(pathPdf))))
  {
      doc.DeletePage(0);
  }

旋转页：

 var pathPdf = "./Pdfium.NetTests/resources/viewer_ref.pdf";
 using (var doc = PdfDocument.Load(new MemoryStream(File.ReadAllBytes(pathPdf))))
 {
     doc.RotatePage(0, PdfRotation.Rotate90);
 }

获取pdf内签名信息：

 var pathPdf = "./Pdfium.NetTests/resources/signature_reason.pdf";
 using (var doc = PdfDocument.Load(new MemoryStream(File.ReadAllBytes(pathPdf))))
 {
     var len = doc.GetSignatureCount();
     for (int i = 0; i < len; i++)
     {
         var sign = doc.GetSignatureObject(i);
         var encoding = sign.GetSubFilter();

         var strSign = sign.GetContents();
         var strSign1 = sign.GetByteRange();

         var strReason = sign.GetReason();
         var strTime = sign.GetTime();

         var press = sign.GetDocMDPPermission();
     }
 }

获取当前页字符信息：

  var pathPdf = "./Pdfium.NetTests/resources/fontText.pdf";
  using (var doc = PdfDocument.Load(new MemoryStream(File.ReadAllBytes(pathPdf))))
  {
      var page0 = doc.Pages[0];
      var infos = page0.GetCharacterInformation();
  }

 

打印：

 var printer = new PdfPrinter("Microsoft Print To PDF");
 //printer.Print(fileName);
 printer.Print(fileName, documentName: "with name");