Pdfium.Net.Free 一个免费的Pdfium的 .net包装器--快速入门

Pdfium.Net.Free 支持

• .NETFramework 4.0

• .NETFramework 4.5

• .NETStandard 2.0

可以和PdfiumViewer.Free共同使用预览pdf，也可以直接引用Pdfium.Net.Free 操作pdf，解决部分.NetCore 调用的问题，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~~

项目地址：

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

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

打开PDF：

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

创建PDF 添加页面：

using (var doc = PdfDocument.CreateNew())
{
    doc.Pages.Add(612, 792);
}

添加文字：

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";
    var page = doc.Pages.Add(612, 792);
    page.AddString(cSharpString, 10, 50, 12, Color.Black);
    doc.Save("./Pdfium.NetTests/AddString.pdf");
}

添加水印：

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");
}

添加图片：

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");
}

pdf每一页转成图片：

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, FpdfRotation.Rotate0, Wrapper.RenderFlags.Annotations | Wrapper.RenderFlags.CorrectFromDpi))
        {
 
        }
    }

pdf页局部转成图片：

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,
            (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
           FpdfRotation.Rotate0, // no rotation
           RenderFlags.None // no render flags
                               ))
        {
 
        }
    }

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();
}

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);
 }

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.GetPDFPage(i);//可多页拆分
  }
}

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.MergePDF(doc1);
}

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;
 }

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))
}

打印：

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