目前.NET 体系下常见的PDF类库有Aspose、QuestPDF、Spire、iTextSharp等，有一说一都挺好用的，我个人特别喜欢QuestPDF它基于 C# Fluent API 提供全面的布局引擎；但是这些库要么属于商业库价格不菲（能理解收费），但是年费太贵了。要么是有条件限制开源的，如Spire开源版本有各种限制。iTextSharp虽然没有限制，但是开源协议不友好（AGPL），用于闭源商业软件属于要挂耻辱柱的行为了。
无意间发现了另一款基于.NET6的跨平台、免费开源（MIT协议）pdf处理库：PDFSharp，该库还有基于.NET Framework的版本https://pdfsharp.net/ ，.NET6版本好像是去年刚发布的，还有一个较为活跃的社区https://forum.pdfsharp.net/。
尝试使用了下，还不错，该有的都有，简单的pdf文件可以直接使用PDFSharp库生成，复杂点的则提供了MigraDoc来编辑。我自己的小应用都已经上生成环境了，个人觉得该库是挺ok的了。
.NET Framework文档站点下有很多例子大家可以看看：
我的使用方式较为粗暴，使用MigraDoc编辑文档表格，再生成PDF文件。有时间再尝试封装个类似于QuestPDF的扩展库，太喜欢Fluent这种形式了。
代码例子让我们来制作下图的pdf吧
新建一个项目，通过Nuget引入PDFsharp、PDFsharp-MigraDoc，若用System.Drawing图形库则不用引用SkiaSharp，我的例子使用SkiaSharp图形库便于跨平台。
首先是字体的导入
因为PDFSharp本身不支持中文字体，但提供了自定义解析器的处理，所以我们先实现下中文字体解析器。先将黑体作为嵌入资源导入项目中，路径是/Fonts/下新建一个文件ChineseFontResolver.cs用来实现我们的中文解析器using PdfSharp.Fonts; using System.Reflection; namespace pdfsharpDemo;/// <summary>/// 中文字体解析器/// </summary>public ChineseFontResolver : IFontResolver{ /// <summary> /// 字体作为嵌入资源所在程序集 /// </summary> public static string FontAssemblyString { get; set; } = "pdfsharpDemo"; /// <summary> /// 字体作为嵌入资源所在命名空间 /// </summary> public static string FontNamespace { get; set; } = "pdfsharpDemo.Fonts"; /// <summary> /// 字体名称 /// </summary> public static FamilyNames { // This implementation considers each font face as its own family. /// <summary> /// 仿宋 /// </summary> public const string SIMFANG = "simfang.ttf"; /// <summary> /// 黑体 /// </summary> public const string SIMHEI = "simhei.ttf"; /// <summary> /// 楷书 /// </summary> public const string SIMKAI = "simkai.ttf"; /// <summary> /// 隶书 /// </summary> public const string SIMLI = "simli.ttf"; /// <summary> /// 宋体 /// </summary> public const string SIMSUN = "simsun.ttf"; /// <summary> /// 宋体加粗 /// </summary> public const string SIMSUNB = "simsunb.ttf"; /// <summary> /// 幼圆 /// </summary> public const string SIMYOU = "simyou.ttf"; } /// <summary> /// Selects a physical font face based on the specified information /// of a required typeface. /// </summary> /// <param name="familyName">Name of the font family.</param> /// <param name="isBold">Set to <c>true</c> when a bold font face /// is required.</param> /// <param name="isItalic">Set to <c>true</c> when an italic font face /// is required.</param> /// <returns> /// Information about the physical font, or null if the request cannot be satisfied. /// </returns> public FontResolverInfo? ResolveTypeface(string familyName, bool isBold, bool isItalic) { // Note: PDFsharp calls ResolveTypeface only once for each unique combination // of familyName, isBold, and isItalic. return new FontResolverInfo(familyName, isBold, isItalic); // Return null means that the typeface cannot be resolved and PDFsharp forwards // the typeface request depending on PDFsharp build flavor and operating system. // Alternatively forward call to PlatformFontResolver. //return PlatformFontResolver.ResolveTypeface(familyName, isBold, isItalic); } /// <summary> /// Gets the bytes of a physical font face with specified face name. /// </summary> /// <param name="faceName">A face name previously retrieved by ResolveTypeface.</param> /// <returns> /// The bits of the font. /// </returns> public byte[]? GetFont(string faceName) { // Note: PDFsharp never calls GetFont twice with the same face name. // Note: If a typeface is resolved by the PlatformFontResolver.ResolveTypeface // you never come here. var name = $"{FontNamespace}.{faceName}"; using Stream stream = Assembly.Load(FontAssemblyString).GetManifestResourceStream(name) ?? throw new ArgumentException("No resource named '" + name + "'."); int num = (int)stream.Length; byte[] array = new byte[num]; stream.Read(array, 0, num); // Return the bytes of a font. return array; }}好了，开始制作我们的pdf吧
// See https://aka.ms/new-console-template for more informationusing Microsoft.Extensions.Configuration;using MigraDoc.DocumentObjectModel;using MigraDoc.DocumentObjectModel.Tables;using MigraDoc.Rendering;using PdfSharp.Drawing;using PdfSharp.Fonts;using PdfSharp.Pdf;using PdfSharp.Pdf.IO;using pdfsharpDemo;using SkiaSharp;using System;using System.IO;using static pdfsharpDemo.ChineseFontResolver;Console.WriteLine("Hello, PDFSharp!");// 设置PDFSharp全局字体为自定义解析器GlobalFontSettings.FontResolver = new ChineseFontResolver();#region pdf页面的基本设置 var document = new Document();var _style = document.Styles["Normal"];//整体样式_style.Font.Name = FamilyNames.SIMHEI;_style.Font.Size = 10;var _tableStyle = document.Styles.AddStyle("Table", "Normal");//表格样式_tableStyle.Font.Name = _style.Font.Name;_tableStyle.Font.Size = _style.Font.Size;var _section = document.AddSection();_section.PageSetup = document.DefaultPageSetup.Clone();_section.PageSetup.PageFormat = PageFormat.A4; //A4纸规格_section.PageSetup.Orientation = Orientation.Landscape;//纸张方向：横向，默认是竖向_section.PageSetup.TopMargin = 50f;//上边距 50_section.PageSetup.LeftMargin = 25f;//左边距 20#endregion//这里采用三个表格实现标题栏、表格内容、底栏提示 //创建一个表格，并且设置边距var topTable = _section.AddTable();topTable.Style = _style.Name;topTable.TopPadding = 0;topTable.BottomPadding = 3;topTable.LeftPadding = 0;var tableWidth = _section.PageSetup.PageHeight - _section.PageSetup.LeftMargin * 2;// 标题栏分为三格float[] topTableWidths = [tableWidth / 2, tableWidth / 2];//生成对应的二列，并设置宽度foreach (var item in topTableWidths){ var column = topTable.AddColumn(); column.Width = item;}//生成行，设置标题var titleRow = topTable.AddRow();titleRow.Cells[0].MergeRight = 1;//向右跨一列（合并列）titleRow.Cells[0].Format.Alignment = ParagraphAlignment.Center;//元素居中var parVlaue = titleRow.Cells[0].AddParagraph();parVlaue.Format = new ParagraphFormat();parVlaue.Format.Font.Bold = true;//粗体parVlaue.Format.Font.Size = 16;//字体大小parVlaue.AddText("我的第一个PDFSharp例子");//生成标题行，这里我们设置两行var row2 = topTable.AddRow();var noCell = row2.Cells[0];noCell.Format.Alignment = ParagraphAlignment.Left;noCell.AddParagraph().AddText($"编号：00000001");var orgNameCell = row2.Cells[1];orgNameCell.Format.Alignment = ParagraphAlignment.Right;orgNameCell.AddParagraph().AddText("单位：PDFSharp研究小组");var row3 = topTable.AddRow();var createAtCell = row3.Cells[0];createAtCell.Format.Alignment = ParagraphAlignment.Left;createAtCell.AddParagraph().AddText($"查询时间：{DateTime.Now.AddDays(-1):yyyy年MM月dd日 HH:mm}");var printTimeCell = row3.Cells[1];printTimeCell.Format.Alignment = ParagraphAlignment.Right;printTimeCell.AddParagraph().AddText($"打印时间：{DateTime.Now:yyyy年MM月dd日 HH:mm}");//表格内容var contentTable = _section.AddTable();contentTable.Style = _style.Name;contentTable.Borders = new Borders{ Color = Colors.Black, Width = 0.25};contentTable.Borders.Left.Width = 0.5;contentTable.Borders.Right.Width = 0.5;contentTable.TopPadding = 6;contentTable.BottomPadding = 0;//这里设置8列好了var tableWidths = new float[8];tableWidths[0] = 30;tableWidths[1] = 60;tableWidths[2] = 40;tableWidths[5] = 60;tableWidths[6] = 80;float w2 = (_section.PageSetup.PageHeight - (_section.PageSetup.LeftMargin * 2) - tableWidths.Sum()) / 2;//假装自适应，哈哈哈tableWidths[3] = w2;tableWidths[4] = w2;//生成列foreach (var item in tableWidths){ var column = contentTable.AddColumn(); column.Width = item; column.Format.Alignment = ParagraphAlignment.Center;}//生成标题行 var headRow = contentTable.AddRow();headRow.TopPadding = 6;headRow.BottomPadding = 6;headRow.Format.Font.Bold = true;headRow.Format.Font.Size = "12";headRow.VerticalAlignment = VerticalAlignment.Center;headRow.Cells[0].AddParagraph().AddText("序号");headRow.Cells[1].AddParagraph().AddText("姓名");headRow.Cells[2].AddParagraph().AddText("性别");headRow.Cells[3].AddParagraph().AddText("家庭地址");headRow.Cells[4].AddParagraph().AddText("工作单位");var cParVlaue = headRow.Cells[5].AddParagraph();"银行卡总额（元）".ToList()?.ForEach(o => cParVlaue.AddChar(o));//自动换行 使用AddCharheadRow.Cells[6].AddParagraph().AddText("联系电话");//内容列，随便填点吧 用元组实现，懒得搞个类了List<(string name, string sex, string addree, string workplace, decimal? amount, string phone)> contentData = new(){ new () {name="张珊",sex="女",addree="市政府宿舍",workplace="市政府",amount=12002M,phone="138********3333"}, new () {name="李思",sex="女",addree="省政府宿舍大楼下的小破店旁边的垃圾桶前面的别墅",workplace="省教育局",amount=220000M,phone="158********3456"}, new () {name="王武",sex="男",addree="凤凰村",workplace="老破小公司",amount=-8765M,phone="199********6543"}, new () {name="",sex="",addree="",workplace="",amount=null,phone=""},};var index = 1;foreach (var (name, sex, addree, workplace, amount, phone) in contentData){ var dataRow = contentTable.AddRow(); dataRow.TopPadding = 6; dataRow.BottomPadding = 6; dataRow.Cells[0].AddParagraph().AddText($"{index++}"); dataRow.Cells[1].AddParagraph().AddText(name); dataRow.Cells[2].AddParagraph().AddText(sex); var addreeParVlaue = dataRow.Cells[3].AddParagraph(); addree?.ToList()?.ForEach(o => addreeParVlaue.AddChar(o));//自动换行 使用AddChar dataRow.Cells[4].AddParagraph().AddText(workplace); dataRow.Cells[5].AddParagraph().AddText(amount?.ToString() ?? ""); dataRow.Cells[6].AddParagraph().AddText(phone);}//空白 段落 分隔下间距Paragraph paragraph = new();// 设置段落格式paragraph.Format.SpaceBefore = "18pt"; // 设置空行高度为 12 磅 document.LastSection.Add(paragraph); // 将段落添加到文档中//底栏提示 var tipsTable = _section.AddTable();tipsTable.Style = _style.Name;tipsTable.TopPadding = 3;var tipsTableColumn = tipsTable.AddColumn();tipsTableColumn.Width = _section.PageSetup.PageHeight - _section.PageSetup.LeftMargin * 2;var tipsParagraph = tipsTable.AddRow().Cells[0].AddParagraph();tipsParagraph.Format.Font.Bold = true;tipsParagraph.Format.Font.Color = Colors.Red; //设置红色tipsParagraph.AddText($"注：隐私信息是我们必须要注重的废话连篇的东西，切记切记，不可忽视，因小失大;");#region 页码_section.PageSetup.DifferentFirstPageHeaderFooter = false;var pager = _section.Footers.Primary.AddParagraph();pager.AddText($"第\t");pager.AddPageField();pager.AddText($"\t页");pager.Format.Alignment = ParagraphAlignment.Center;#endregion//生成PDFvar pdfRenderer = new PdfDocumentRenderer();using var memoryStream = new MemoryStream();pdfRenderer.Document = document;pdfRenderer.RenderDocument();pdfRenderer.PdfDocument.Save(memoryStream);var pdfDocument = PdfReader.Open(memoryStream);//为了跨平台 用的是SkiaSharp，大家自己转为System.Drawing实现即可，较为简单就不写了#region 水印using var watermarkMemoryStream = new MemoryStream();var watermarkImgPath = "D:\\logo.png";using var watermarkFile = System.IO.File.OpenRead(watermarkImgPath);// 读取文件 using var fileStream = new SKManagedStream(watermarkFile);using var bitmap = SKBitmap.Decode(fileStream);//设置半透明var transparent = new SKColor(0, 0, 0, 0);for (int w = 0; w < bitmap.Width; w++){ for (int h = 0; h < bitmap.Height; h++) { SKColor c = bitmap.GetPixel(w, h); SKColor newC = c.Equals(transparent) ? c : new SKColor(c.Red, c.Green, c.Blue, 70); bitmap.SetPixel(w, h, newC); }}using var resized = bitmap.Resize(new SKImageInfo(200, 80), SKFilterQuality.High);using var newImage = SKImage.FromBitmap(resized);newImage.Encode(SKEncodedImageFormat.Png, 90).SaveTo(watermarkMemoryStream); // 保存文件 using var image = XImage.FromStream(watermarkMemoryStream);var xPoints = 6;var yPoints = 4;for (int i = 0; i <= xPoints; i++){ var xPoint = image.PointWidth * i * 1.2; var xTranslateTransform = xPoint + image.PointWidth / 2; for (int j = 0; j <= yPoints; j++) { var yPoint = image.PointHeight * j * 1.2; var yTranslateTransform = yPoint + image.PointHeight / 8; foreach (var page in pdfDocument.Pages) { using var xgr = XGraphics.FromPdfPage(page, XGraphicsPdfPageOptions.Prepend); xgr.TranslateTransform(xTranslateTransform, yTranslateTransform); xgr.RotateTransform(-45); xgr.TranslateTransform(-xTranslateTransform, -yTranslateTransform); xgr.DrawImage(image, xPoint, yPoint, 200, 80); } }}#endregionpdfDocument.Save(memoryStream);var outputPdfFilePath = "D:\\pdfdemo.pdf";//保存到本地using var fs = new FileStream(outputPdfFilePath, FileMode.Create);byte[] bytes = new byte[memoryStream.Length];memoryStream.Seek(0, SeekOrigin.Begin);memoryStream.Read(bytes, 0, (int)memoryStream.Length);fs.Write(bytes, 0, bytes.Length);Console.WriteLine("生成成功!");至此我们就制作好了一个简单的pdf，当然了这里没有加上文件信息那些，仅仅是生成内容罢了，有那些需要的可以自己根据文档站点看看如何设置。
源码地址：https://gitee.com/huangguishen/MyFile/tree/master/PDFSharpDemo
