ASP.NET HTML转PDF

通过Url地址或者html内容生成到PDF文件,并部署到IIS,转换内容不支持Webpack构建的前端项目。


这里使用的是TuesPechkin,引用下面2个Nuget包

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封装简单工具类

   /// <summary>
    /// html转pdf帮助类
    /// </summary>
    public static class HtmlToPdfHelper
    {
        private static readonly string _fileDir = "htmlToPdf";
        private static readonly string _savePath = System.Web.Hosting.HostingEnvironment.MapPath("/" + _fileDir);
        private static IConverter _converter = null; //官方要求在程序生命周期内,只能实例化一次
        private static string _domainUrl;

        /// <summary>
        /// 获取当前站点域名
        /// </summary>
        /// <returns></returns>
        public static string DomainUrl
        {
            get
            {
                Uri uri = HttpContext.Current.Request.Url;
                _domainUrl = uri.Scheme + "://" + uri.Host;
                if (!uri.IsDefaultPort)
                {
                    _domainUrl += ":" + uri.Port;
                }
                return _domainUrl;
            }
        }

        static HtmlToPdfHelper()
        {
            _converter =
                new ThreadSafeConverter(
                    new RemotingToolset<PdfToolset>(
                        new WinAnyCPUEmbeddedDeployment(
                            new TempFolderDeployment())));

            //_converter.Begin += ConverterOnBegin;
            //_converter.PhaseChange += ConverterOnPhaseChange;
            //_converter.ProgressChange += ConverterOnProgressChange;
            //_converter.Finish += ConverterOnFinish;
            _converter.Warning += new EventHandler<WarningEventArgs>((o, w) =>
            {
                Console.WriteLine("HtmlToPdfHelper类,html转换PDF,产生警告信息:" + w.WarningMessage);
            });
            _converter.Error += new EventHandler<TuesPechkin.ErrorEventArgs>((o, e) =>
            {
                Console.WriteLine("HtmlToPdfHelper类,html转换PDF,产生错误信息:" + e.ErrorMessage);
            });
        }

        /// <summary>
        /// 转换为pdf字节
        /// </summary>
        /// <param name="doc"></param>
        /// <returns></returns>
        private static byte[] Filing(IDocument doc)
        {
            byte[] result = _converter.Convert(doc);
            return result;
        }

        /// <summary>
        /// 构建PDF服务器访问地址
        /// </summary>
        /// <param name="pdfName"></param>
        /// <returns></returns>
        private static string BuildUrl(string pdfName)
        {
            return $@"{DomainUrl}/{_fileDir}/{pdfName}.pdf";
        }

        /// <summary>
        /// 构建PDF保存路径
        /// </summary>
        /// <param name="pdfName"></param>
        /// <returns></returns>
        private static string BuildSaveSrc(string pdfName)
        {
            return $@"{_savePath}\{pdfName}.pdf";
        }

        /// <summary>
        /// 查找已转换的PDF文件
        /// </summary>
        /// <param name="pdfName">已保存PDF名称</param>
        /// <returns>返回保存Url地址</returns>
        private static string FindSaveHtmlPdf(string pdfName)
        {
            //把文件读进文件流 
            var fileSrc = BuildSaveSrc(pdfName);
            if (!File.Exists(fileSrc))
            {
                return string.Empty;
            }
            return BuildUrl(pdfName);
        }

        /// <summary>
        /// 保存已转换的PDF文件
        /// </summary>
        /// <param name="fileName">PDF文件名</param>
        /// <param name="bf">保存字节集</param>
        /// <returns>保存成功返回url</returns>
        private static string SaveHtmlToPdfFile(string fileName, byte[] bf)
        {
            var path = _savePath;
            if (!Directory.Exists(path))
            {
                Directory.CreateDirectory(path);
            }
            System.IO.File.WriteAllBytes(BuildSaveSrc(fileName), bf);
            return BuildUrl(fileName);
        }

        /// <summary>
        /// 根据类型转换PDF为字节
        /// </summary>
        /// <param name="document">保存文档</param>
        /// <param name="type">保存的类型</param>
        /// <returns></returns>
        private static byte[] BuildDocumentByType(string document, EHtmlToPdfDocumentType type)
        {
            byte[] saveBuffer = null;
            if (type == EHtmlToPdfDocumentType.HtmlUrl)
            {
                saveBuffer = ConvertHtmlUrlToPDF(document);
            }
            else if (type == EHtmlToPdfDocumentType.HtmlText)
            {
                saveBuffer = ConvertHtmlTextToPDF(document);
            }
            return saveBuffer;
        }

        /// <summary>
        /// 转换htmltext为PDF
        /// </summary>
        /// <param name="htmlText">html文档内容</param>
        /// <returns></returns>
        public static byte[] ConvertHtmlTextToPDF(string htmlText)
        {
            if (string.IsNullOrWhiteSpace(htmlText))
            {
                new ArgumentNullException("htmlText", "html的内容不能为空");
            }

            var document = new HtmlToPdfDocument
            {
                GlobalSettings = { },
                Objects = {
                new ObjectSettings {
                        HtmlText = htmlText,
                        WebSettings =new WebSettings
                        {
                            DefaultEncoding="UTF-8",
                            LoadImages=true,
                        }
                    }
                },

            };
            var result = _converter.Convert(document);
            return result;
        }

        /// <summary>
        /// 转换htmlUrl为PDF
        /// </summary>
        /// <param name="htmlText">html文档内容</param>
        /// <returns></returns>
        public static byte[] ConvertHtmlUrlToPDF(string htmlUrl)
        {
            if (string.IsNullOrWhiteSpace(htmlUrl))
            {
                new ArgumentNullException("htmlUrl", "html的Url地址不能为空");
            }

            var doc = new HtmlToPdfDocument();
            doc.Objects.Add(new ObjectSettings { PageUrl = htmlUrl });

            byte[] result = Filing(doc);
            return result;
        }

        /// <summary>
        /// 获取Html转换后的PDF文件Url(如果文件不存在,并先执行保存,在返回url地址)
        /// </summary>
        /// <param name="pdfName">要保存PDF名称</param>
        /// <param name="document">要保存的Hmtl文档内容,(例如,htmlTXT,htmlurl)</param>
        /// <param name="type">保存的type类型</param>
        /// <param name="IsCover">是否覆盖(默认不覆盖)</param>
        /// <returns></returns>
        public static string GetHtmlToPdfSaveUrl(string pdfName, string document, EHtmlToPdfDocumentType type, bool IsCover = false)
        {
            string pdfSaveUrl = FindSaveHtmlPdf(pdfName);
            if (string.IsNullOrEmpty(pdfSaveUrl) || IsCover)
            {
                //获取转换成功后PDF字节
                byte[] saveBuffer = BuildDocumentByType(document, type);
                //返回保存成功后PDF文件url
                return SaveHtmlToPdfFile(pdfName, saveBuffer);
            }
            return pdfSaveUrl;
        }

        /// <summary>
        /// 下载Html转换后的PDF文件字节流(如果文件不存在,并先执行保存,在返回下载字节流)
        /// </summary>
        /// <param name="pdfName">要保存PDF名称</param>
        /// <param name="document">要保存的Hmtl文档内容,(例如,htmlTXT,htmlurl)</param>
        /// <param name="type">保存的type类型</param>
        /// <param name="IsCover">是否覆盖(默认不覆盖)</param>
        /// <returns></returns>
        public static byte[] DownloadHtmlToPdf(string pdfName, string document, EHtmlToPdfDocumentType type, bool IsCover = false)
        {
            byte[] saveBuffer = DownloadSaveHtmlToPdf(pdfName);
            if (saveBuffer == null || IsCover)
            {
                //获取转换成功后PDF字节
                saveBuffer = BuildDocumentByType(document, type);
                //保存PDF文件
                SaveHtmlToPdfFile(pdfName, saveBuffer);
                return saveBuffer;
            }
            return saveBuffer;
        }

        /// <summary>
        /// 获取已存在服务器上的PDF文件字节
        /// </summary>
        /// <param name="pdfName">文件名称</param>
        /// <returns></returns>
        public static byte[] DownloadSaveHtmlToPdf(string pdfName)
        {
            //把文件读进文件流 
            var fileSrc = BuildSaveSrc(pdfName);
            if (!File.Exists(fileSrc))
            {
                return null;
            }
            FileStream fs = new FileStream(fileSrc, FileMode.Open);
            byte[] file = new byte[fs.Length];
            fs.Read(file, 0, file.Length);
            fs.Close();
            return file;
        }
    }

    /// <summary>
    /// 文档转换类型
    /// </summary>
    public enum EHtmlToPdfDocumentType
    {
        HtmlUrl = 0,
        HtmlText = 1,
    }

测试代码

 public string GetHtmlToPdf(string pdfName, string url)
  {

            if (string.IsNullOrWhiteSpace(url))
            {
                string[] arrs = new string[] { "http://www.baidu.com", "https://news.qq.com/", "https://www.sogou.com/" };
                var index = new Random().Next(0, arrs.Length);
                url = arrs[index];
            }
            if (string.IsNullOrWhiteSpace(pdfName))
            {
                pdfName = DateTime.Now.ToString("yyyyMMdd_HHmmss");
            }

            var res = HtmlToPdfHelper.GetHtmlToPdfSaveUrl(pdfName, url, EHtmlToPdfDocumentType.HtmlUrl);
            return res;
}

测试调用

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转换结果
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