c#用iTextSharp生成pdf文档

﹏ヽ暗。殇╰゛Y 2023-06-17 07:56 7阅读 0赞

# c\#用iTextSharp生成pdf文档 #

在应用中有时需要生成pdf文档。在vs中用nuget添加 iTextSharp的引用，就可以方便的操作pdf了

先上一段常用操作的代码

using iTextSharp.text.pdf;
    using System.IO;
    using iTextSharp.text;
    
    namespace Net.BLL.Pdf
    {
        /// <summary>
        /// PDF文档操作类
        /// </summary>
        //------------------调用--------------------------
        //PDFOperation pdf = new PDFOperation();
        //pdf.Open(filepath); 或 pdf.Open(new FileStream(pdfNewFile, FileMode.Create));
        //pdf.SetBaseFont(@"C:\Windows\Fonts\SIMHEI.TTF");
        //pdf.AddParagraph("测试文档（生成时间：" + DateTime.Now + "）", 15, 1, 20, 0, 0);
        //pdf.Close();
        //-------------------------------
        public class PDFOperation
        {
            #region 构造函数
            /// <summary>
            /// 构造函数,默认A4大小
            /// </summary>
            public PDFOperation()
            {
                rect = PageSize.A4;
                document = new Document(rect);
            }
    
            /// <summary>
            /// 构造函数
            /// </summary>
            /// <param name="type">页面大小(如"A4")可选值A1-A10,B1,B2等 参考PageSize的值</param>
            public PDFOperation(string type)
            {
                SetPageSize(type);
                document = new Document(rect);
            }
    
            /// <summary>
            /// 构造函数
            /// </summary>
            /// <param name="type">页面大小(如"A4") 可选值A1-A10,B1,B2等 参考PageSize的值</param>
            /// <param name="marginLeft">内容距左边框距离</param>
            /// <param name="marginRight">内容距右边框距离</param>
            /// <param name="marginTop">内容距上边框距离</param>
            /// <param name="marginBottom">内容距下边框距离</param>
            public PDFOperation(string type, float marginLeft, float marginRight, float marginTop, float marginBottom)
            {
                SetPageSize(type);
                document = new Document(rect, marginLeft, marginRight, marginTop, marginBottom);
            }
            #endregion
    
            #region 私有字段
            private Font font;
            private Rectangle rect;  //文档大小
            private Document document;//文档对象
            private BaseFont basefont;//字体
            private PdfWriter pdfWriter; 
            #endregion
    
            #region 设置字体
            /// <summary>
            /// 设置字体 D:\\Windows\\Fonts\\SIMSUN.TTC 如该字体，没有可以从网上下载后放在系统字体文件夹下
            /// 不设置的话默认字体不支持中文
            /// </summary>
            public void SetBaseFont(string path)
            {
                basefont = BaseFont.CreateFont(path, BaseFont.IDENTITY_H, BaseFont.NOT_EMBEDDED);
            }
    
            /// <summary>
            /// 设置字体
            /// </summary>
            /// <param name="size">字体大小</param>
            public void SetFont(float size)
            {
                font = new Font(basefont, size);
            }
            #endregion
    
            #region 设置页面大小
            /// <summary>
            /// 设置页面大小
            /// </summary>
            /// <param name="type">页面大小(如"A4") 可选值A1-A10,B1,B2等 参考PageSize的值</param>
            public void SetPageSize(string type)
            {
                switch (type.Trim())
                {
                    case "A4":
                        rect = PageSize.A4;
                        break;
                    case "A8":
                        rect = PageSize.A8;
                        break;
                }
            }
            #endregion
    
            #region 实例化文档
            /// <summary>
            /// 实例化文档
            /// </summary>
            /// <param name="os">文档相关信息（如路径，打开方式等）</param>
            public void GetInstance(Stream os)
            {
                pdfWriter = PdfWriter.GetInstance(document, os);
            }
            #endregion
    
            #region 打开文档对象
            /// <summary>
            /// 打开文档对象
            /// </summary>
            /// <param name="os">文档相关信息（如路径，打开方式等）</param>
            public void Open(Stream os)
            {
                GetInstance(os);
                document.Open();
            }
    
            /// <summary>
            /// 打开文档对象
            /// </summary>
            /// <param name="pdfNewFile">文档路径</param>
            public void Open(string pdfNewFile)
            {
                pdfWriter = PdfWriter.GetInstance(document, new FileStream(pdfNewFile, FileMode.Create));
                document.Open();
            }
            #endregion
    
            #region 关闭打开的文档
            /// <summary>
            /// 关闭打开的文档
            /// </summary>
            public void Close()
            {
                document.Close();
                pdfWriter.Close();
            }
            #endregion
    
            #region 添加段落
            /// <summary>
            /// 添加段落
            /// </summary>
            /// <param name="contents">内容</param>
            /// <param name="fontsize">字体大小</param>
            public void AddParagraph(string contents, float fontsize)
            {
                SetFont(fontsize);
                Paragraph pra = new Paragraph(contents, font);
                document.Add(pra);
            }
    
            /// <summary>
            /// 添加段落,文本段
            /// </summary>
            /// <param name="contents">内容</param>
            /// <param name="fontsize">字体大小</param>
            /// <param name="Alignment">对齐方式（1为居中，0为居左，2为居右）</param>
            /// <param name="SpacingAfter">段后空行数（0为默认值）</param>
            /// <param name="SpacingBefore">段前空行数（0为默认值）</param>
            /// <param name="MultipliedLeading">行间距（0为默认值）</param>
            public void AddParagraph(string contents, float fontsize, int Alignment, float SpacingAfter, float SpacingBefore, float MultipliedLeading)
            {
                SetFont(fontsize);
                Paragraph pra = new Paragraph(contents, font);
                pra.Alignment = Alignment;
                if (SpacingAfter != 0)
                {
                    pra.SpacingAfter = SpacingAfter;
                }
                if (SpacingBefore != 0)
                {
                    pra.SpacingBefore = SpacingBefore;
                }
                if (MultipliedLeading != 0)
                {
                    pra.MultipliedLeading = MultipliedLeading;
                }
                document.Add(pra);
            }
    
            #endregion
    
            #region 添加图片
            /// <summary>
            /// 添加图片
            /// </summary>
            /// <param name="path">图片路径</param>
            /// <param name="Alignment">对齐方式（1为居中，0为居左，2为居右）</param>
            /// <param name="newWidth">图片宽（0为默认值，如果宽度大于页宽将按比率缩放）</param>
            /// <param name="newHeight">图片高</param>
            public void AddImage(string path, int Alignment, float newWidth, float newHeight)
            {
                Image img = Image.GetInstance(path);
                img.Alignment = Alignment;
                if (newWidth != 0)
                {
                    img.ScaleAbsolute(newWidth, newHeight);
                }
                else
                {
                    if (img.Width > PageSize.A4.Width)
                    {
                        img.ScaleAbsolute(rect.Width, img.Width * img.Height / rect.Height);
                    }
                }
                document.Add(img);
            }
            #endregion
    
            #region 添加链接、点
            /// <summary>
            /// 添加链接
            /// </summary>
            /// <param name="Content">链接文字</param>
            /// <param name="FontSize">字体大小</param>
            /// <param name="Reference">链接地址</param>
            public void AddAnchorReference(string Content, float FontSize, string Reference)
            {
                SetFont(FontSize);
                Anchor auc = new Anchor(Content, font);
                auc.Reference = Reference;
                document.Add(auc);
            }
            /// <summary>
            /// 添加链接点
            /// </summary>
            /// <param name="Content">链接文字</param>
            /// <param name="FontSize">字体大小</param>
            /// <param name="Name">链接点名</param>
            public void AddAnchorName(string Content, float FontSize, string Name)
            {
                SetFont(FontSize);
                Anchor auc = new Anchor(Content, font);
                auc.Name = Name;
                document.Add(auc);
            }
            #endregion
    
            #region === 其它属性设置 ===
            /// <summary>
            /// 设置title
            /// </summary>
            /// <param name="title"></param>
            public void SetTitle(string title)
            {
                document.AddTitle(title);
            }
    
            /// <summary>
            /// 设置subject
            /// </summary>
            /// <param name="subject"></param>
            public void SetSubject(string subject)
            {
                document.AddSubject(subject);
            }
    
            /// <summary>
            /// 设置keywords
            /// </summary>
            /// <param name="keywords"></param>
            public void SetKeywords(string keywords)
            {
                document.AddKeywords(keywords);
            }
    
            /// <summary>
            /// 设置creator
            /// </summary>
            /// <param name="creator"></param>
            public void SetCreator(string creator)
            {
                document.AddCreator(creator);
            }
    
            /// <summary>
            /// 设置author
            /// </summary>
            /// <param name="author"></param>
            public void SetAuthor(string author)
            {
                document.AddAuthor(author);
            }
            #endregion
        }
    }

如何调用代码中详细的说明，但是你会发现，操作pdf文档过程中添加文本，添加图片这些常见的方法都没有问题，但最终生成出来的文档却差强人意

原因在哪？当然是排版的问题，要调整好文本段落与图片的布局，位置很是麻烦。虽然iTextSharp支持图片，文本的插入位置设置，但用代码来设置还是很费劲。

最好的方式就是先做好pdf文档的模板，利用模板来生成想要的pdf文档，这样省时省力，但前提就是模板文件要准备好。

模板文件可以利用pdf编辑器生成，你可以考虑用Adobe Acrobat DC系列的工具来做，做文档的过程中最重要的就是在文档中添加好对应的表单，在代码中分别在对应的表单域名中添加对应的元素。这样的话，位置，样式统统可以在模板文档中设置中，代码中只管添加元素进去。

下面是利用模板来生成pdf文档的代码

using System;
    using System.Collections.Generic;
    using iTextSharp.text.pdf;
    using System.IO;
    using iTextSharp.text;
    
    
    
    namespace Net.BLL.Pdf
    {
        /// <summary>
        /// 使用pdf模板方式创建pdf的帮助类
        /// </summary>
        //------- 调用示例 --------
        //  Net.BLL.Pdf.PdfWithTemplateHelper pdf = new Net.BLL.Pdf.PdfWithTemplateHelper();
        //  pdf.Open("E:\\PdfTest\\mytemplate.pdf", "E:\\PdfTest\\test.pdf");
        //  pdf.PutText("txttitle", "pdf生成测试");
        //  pdf.PutText("txtuser001", "Me \r\n生日：1988-8-9 \r\n爱好：运动、健身、旅游");
        //  pdf.PutImage(1, "img001", "e:/PdfTest/pic01.jpg");
        //  pdf.PutText("txtuser002", "肖鼠:鼠年出生的人的本命佛是千手观音，得千手观音庇佑。肖鼠的人财运好，在十二生肖中属于富贵型！");
        //  pdf.PutImage(1, "img002", "e:/PdfTest/pic02.jpg");
        //  pdf.PutText("txtbuddha001", "生命在于运动！人生不止，运动不息!");
        //  pdf.Close();
        //--------- end -----------
        public class PdfWithTemplateHelper
        {
            PdfReader pdfReader = null;
            PdfStamper pdfStamper = null;
            AcroFields pdfFormFields = null;
            PdfWriter pdfWriter = null;
    
            public PdfWithTemplateHelper()
            {
    
            }
    
            /// <summary>
            /// 创建文档
            /// </summary>
            /// <param name="pdfTemplateFile">模板文件路径</param>
            /// <param name="pdfNewFile">要生成的文档路径</param>
            public void Open(string pdfTemplateFile, string pdfNewFile)
            {
                pdfReader = new PdfReader(pdfTemplateFile);
                pdfStamper = new PdfStamper(pdfReader, new FileStream(pdfNewFile, FileMode.OpenOrCreate));
                pdfFormFields = pdfStamper.AcroFields;
                pdfStamper.FormFlattening = true;
            }
            
            /// <summary>
            /// 关闭并保存文档
            /// </summary>
            public void Close()
            {
                pdfStamper.Close();
                pdfReader.Close();
    
                pdfStamper = null;
                pdfReader = null;
                pdfFormFields = null;
            }
    
            /// <summary>
            /// 批量添加图片
            /// </summary>
            /// <param name="pageIndex">页码</param>
            /// <param name="fieldName">表单域名称</param>
            /// <param name="imageFile">图片文件</param>
            /// <param name="rowCount"></param>
            /// <param name="colCount"></param>
            /// <param name="space"></param>
            /// <param name="isScale">是否按比例缩放</param>
            /// <param name="isSquare">是否正方形</param>
            /// <returns></returns>
            public bool PutImageMatrix(int pageIndex, string fieldName, List<string> imageFile, int rowCount, int colCount, int space = 5, bool isScale = true, bool isSquare = false)
            {
    
                PdfContentByte pdfContentByte = pdfStamper.GetOverContent(pageIndex);
                if (pdfContentByte == null)
                {
                    return false;
                }
    
                var positions = pdfFormFields.GetFieldPositions(fieldName);
                if (positions.Count == 0)
                {
                    return false;
                }
    
                AcroFields.FieldPosition fieldPosition = positions[0];
                Rectangle rect = fieldPosition.position;
    
                float left = rect.Left;
                float top = rect.Top;
                float bottom = rect.Bottom;
                float width = rect.Width;
                float height = rect.Height;
    
                float cellH = (height - space * (rowCount + 1)) / rowCount;
                float cellW = (width - space * (colCount + 1)) / colCount;
    
    
                int index = 0;
                for (int row = rowCount - 1; row >= 0; row--)
                {
                    float posBotton = bottom + (cellH + space) * row + space;
    
                    for (int col = 0; col < colCount; col++)
                    {
                        float posLeft = left + (cellW + space) * col + space;
    
                        if (index < imageFile.Count)
                        {
                            Image image = Image.GetInstance(imageFile[index]);
    
                            if (isScale)
                            {
                                image.SetAbsolutePosition(posLeft, posBotton);
                                image.ScaleAbsolute(cellW, cellH);
                            }
                            else
                            {
                                Single imageWidth = image.Width;
                                Single imageHeight = image.Height;
    
                                if (isSquare)
                                {
                                    imageWidth = Math.Min(image.Width, image.Height);
                                    imageHeight = Math.Min(image.Width, image.Height);
                                }
    
                                Rectangle rectDst = new Rectangle(0, 0, 0, 0);
                                rectDst.Left = posLeft;
                                rectDst.Right = posLeft + cellW;
                                rectDst.Bottom = posBotton;
                                rectDst.Top = posBotton + cellH;
                                Rectangle rect1 = GetValidRect(rectDst, imageWidth, imageHeight);
                                image.SetAbsolutePosition(rect1.Left, rect1.Bottom);
                                image.ScaleAbsolute(rect1);
                            }
    
                            pdfContentByte.AddImage(image);
                        }
    
                        index++;
                    }
                }
    
                return true;
            }
    
            /// <summary>
            /// 添加图片
            /// </summary>
            /// <param name="pageIndex">页码</param>
            /// <param name="fieldName">表单域名称</param>
            /// <param name="imageFile">图片文件</param>
            /// <param name="isScale">是否缩放</param>
            /// <returns></returns>
            public bool PutImage(int pageIndex, string fieldName, string imageFile, bool isScale = true)
            {
                PdfContentByte pdfContentByte = pdfStamper.GetOverContent(pageIndex);
                if (pdfContentByte == null)
                {
                    return false;
                }
    
                var positions = pdfFormFields.GetFieldPositions(fieldName);
                if (positions.Count == 0)
                {
                    return false;
                }
    
                AcroFields.FieldPosition fieldPosition = positions[0];
                Rectangle rectDst = fieldPosition.position;
    
                Image image = Image.GetInstance(imageFile);
    
                if (isScale)
                {
                    image.SetAbsolutePosition(rectDst.Left, rectDst.Bottom);
                    image.ScaleAbsolute(rectDst);
                }
                else
                {
                    Single imageWidth = image.Width;
                    Single imageHeight = image.Height;
                    Rectangle rect = GetValidRect(rectDst, imageWidth, imageHeight);
                    image.SetAbsolutePosition(rect.Left, rect.Bottom);
                    image.ScaleAbsolute(rect);
                }
    
                pdfContentByte.AddImage(image);
    
                return true;
            }
    
            /// <summary>
            /// 添加文本内容
            /// </summary>
            /// <param name="fieldName">表单域名称</param>
            /// <param name="str">文本内容</param>
            /// <returns></returns>
            public bool PutText(string fieldName, string str)
            {
                BaseFont bf = BaseFont.CreateFont(BaseFont.HELVETICA, BaseFont.CP1252, BaseFont.NOT_EMBEDDED);
                BaseFont simheiBase = BaseFont.CreateFont("D:\\Windows\\Fonts\\SIMSUN.TTC,1", BaseFont.IDENTITY_H, BaseFont.EMBEDDED);
                pdfFormFields.AddSubstitutionFont(simheiBase);
    
                pdfFormFields.SetField(fieldName, str);
    
    
                return true;
            }
    
    
            Rectangle GetValidRect(Rectangle rectDst, Single imageWith, Single imageHeight)
            {
                Rectangle rect = new Rectangle(0, 0);
    
                double dRatio0 = ((double)rectDst.Width) / rectDst.Height;
                double dRatio1 = ((double)imageWith) / imageHeight;
                double ratio = 0;
                if (dRatio1 > dRatio0)
                {
                    ratio = ((double)rectDst.Width) / imageWith;
                    double realHeight = imageHeight * ratio;
    
                    double diffHeight = (rectDst.Height - realHeight) / 2;
                    rect.Left = rectDst.Left;
                    rect.Top = (float)(rectDst.Top - diffHeight);
                    rect.Right = rectDst.Right;
                    rect.Bottom = (float)(rectDst.Bottom + diffHeight);
                }
                else
                {
                    ratio = ((double)rectDst.Height) / imageHeight;
                    double realWidth = imageWith * ratio;
    
                    double diffWidth = (rectDst.Width - realWidth) / 2;
                    rect.Left = (float)(rectDst.Left + diffWidth);
                    rect.Top = rectDst.Top;
                    rect.Right = (float)(rectDst.Right - diffWidth);
                    rect.Bottom = rectDst.Bottom;
                }
    
                return rect;
            }
    
        }
    }