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  • (转)Dinktopdf在.net core项目里将Html转成PDF(支持liunx)

    Dinktopdf  :   .Net Core对 wkhtmltopdf 库的封装, 使用Webkit引擎将html转换成pdf.

    源码地址: https://github.com/rdvojmoc/DinkToPdf

    使用比较简单,直接把github里的示例代码放到你的.net core项目里。

    注意:要记得把libwkhtmltox库放到项目的根目录里,并在visual studio里设置“如果较新则复制“

    dll是window, so是linux, dylib应该是mac os

    如果从github下载慢,你也可以从码云网站下载

    https://gitee.com/ofri/DinkToPdf

    注: linux或docker容器需要安装 libgdiplus   否则会提示找不到libwkhtmltox

    apt-get update

    apt-get install libgdiplus

    在Startup.cs中添加:

    services.AddSingleton(typeof(IConverter), new SynchronizedConverter(new PdfTools()));//DinkToPdf注入
    

    创建IPDFService

    using System;
    namespace HtmlToPdf.Services
    {
        /// <summary>
        /// 与pdf相关
        /// </summary>
        public interface IPDFService
        {
            /// <summary>
            /// 创建PDF
            /// </summary>
            /// <param name="htmlContent">传入html字符串</param>
            /// <returns></returns>
            byte[] CreatePDF(string htmlContent);
        }
    }
    

    创建PDFService

    using System;
    using DinkToPdf;
    using DinkToPdf.Contracts;
    
    namespace HtmlToPdf.Services
    {
        /// <summary>
        /// 与pdf相关
        /// </summary>
        public class PDFService : IPDFService
        {
            private IConverter _converter;
            public PDFService(IConverter converter)
            {
                _converter = converter;
            }
    
            /// <summary>
            /// 创建PDF
            /// </summary>
            /// <param name="htmlContent">传入html字符串</param>
            /// <returns></returns>
            public byte[] CreatePDF(string htmlContent)
            {
                var globalSettings = new GlobalSettings
                {
                    ColorMode = ColorMode.Color,
                    Orientation = Orientation.Portrait,
                    PaperSize = PaperKind.A4,
                    //Margins = new MarginSettings
                    //{
                    //    Top = 10,
                    //    Left = 0,
                    //    Right = 0,
                    //},
                    DocumentTitle = "PDF Report",
                };
    
                var objectSettings = new ObjectSettings
                {
                    PagesCount = true,
                    HtmlContent = htmlContent,
                    // Page = "www.baidu.com", //USE THIS PROPERTY TO GENERATE PDF CONTENT FROM AN HTML PAGE  这里是用现有的网页生成PDF
                    //WebSettings = { DefaultEncoding = "utf-8", UserStyleSheet = Path.Combine(Directory.GetCurrentDirectory(), "assets", "styles.css") },
                    WebSettings = { DefaultEncoding = "utf-8" },
                    //HeaderSettings = { FontName = "Arial", FontSize = 9, Right = "Page [page] of [toPage]", Line = true },
                    //FooterSettings = { FontName = "Arial", FontSize = 9, Line = true, Center = "Report Footer" }
                };
    
                var pdf = new HtmlToPdfDocument()
                {
                    GlobalSettings = globalSettings,
                    Objects = { objectSettings }
                };
    
                var file = _converter.Convert(pdf);
    
                //return File(file, "application/pdf");
    
                return file;
    
            }
        }
    }
    

    在Startup.cs中依赖注入:

    services.AddTransient<IPDFService, PDFService>();
    

    创建TemplateGenerator,生成html字符串

    using System;
    using System.Text;
    
    namespace HtmlToPdf
    {
        public static class TemplateGenerator
        {
            /// <summary>
            /// 获取HTML字符串
            /// </summary>
            /// <returns></returns>
            public static string GetPDFHTMLString()
            {
    
                StringBuilder sb = new StringBuilder();
    
                sb.Append(@"
    <html>
      <head>
        <meta http-equiv='Content-Type' content='text/html; charset=utf-8' />
        <style>
          
        </style>
      </head>
    
      <body>
        <div>
            这是一个网页!
        </div>
      </body>
    </html>
                ");
    
                return sb.ToString();
            }
        }
    }
    

    修改ValuesController

    using System;
    using System.Collections.Generic;
    using System.Linq;
    using System.Threading.Tasks;
    using HtmlToPdf.Services;
    using Microsoft.AspNetCore.Mvc;
    
    namespace HtmlToPdf.Controllers
    {
        [Route("api/[controller]")]
        [ApiController]
        public class ValuesController : ControllerBase
        {
            private IPDFService _PDFService;
    
            public ValuesController(IPDFService pDFService)
            {
                _PDFService = pDFService;
            }
    
            [HttpGet("pdf")]
            public FileResult GetPDF()
            {
                //获取html模板
                var htmlContent = TemplateGenerator.GetPDFHTMLString();
    
                //生成PDF
                var pdfBytes = _PDFService.CreatePDF(htmlContent);
    
                return File(pdfBytes, "application/pdf");
            }
        }
    }
    

    测试:
    浏览器输入 https://localhost:5001/api/values/pdf

    遇到的问题

    1.不能发布到linux

    这个版本可以在liunx使用,net core 3.1 可以。

    2.生成1次pdf,第2次cpu100%

    Synchronized converter
    Use this converter in multi threaded applications and web servers. Conversion tasks are saved to blocking collection and executed on a single thread.

    var converter = new SynchronizedConverter(new PdfTools());
    

    因为注入的方式错了。IConverter converter 已经注入为单例了,

    services.AddSingleton(typeof(IConverter), new SynchronizedConverter(new PdfTools()));//DinkToPdf注入
    

    所以直接在service注入使用。
    ————————————————
    ASP.NET Core html生成pdf
    作者:GongZH丶
    链接:https://www.jianshu.com/p/81ff83d18534
    ————————————————
    如何使用Dinktopdf在.net core项目里将Html转成PDF
    作者:omage
    链接:https://blog.csdn.net/omage/article/details/114011447

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  • 原文地址:https://www.cnblogs.com/tangge/p/14582341.html
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