asp文件用什么打开|如何使asp自动生成html

asp文件用什么打开|如何使asp自动生成html）

因个人需求，需要将html格式转换成PDF并加上水印图片。于是乎第一次接触这种需求的小菜鸟博主我，在某度搜索引擎上不断地查阅关键字资料、踩坑，终于有了一个相应的解决方案。以下是解决步骤，记录下来方便以后的回顾，以及各位大神们的品鉴。

  1、在 NuGet 搜索 itextsharp 关键字 下载以下截图圈中的两个包，一般下载完后项目会自动引用。

  2、在项目文件中引入以下命名空间|建议下面提及的代码封装成类库，方便项目间调用，个人取舍）

  3、Html字符串转pdf文件流，加水印图片以及未加水印重载 精简帮助类|由博主踩坑整理，仅完成个人业务需求）

1     /// <summary> 2     /// Html字符串转PDF输出帮助类 3     /// </summary> 4     public class HtmlToPdfHelper 5     { 6         #region HtmlToPDF 7  8         /// <summary> 9         /// 判断是否有乱码10         /// </summary>11         /// <param name="txt"></param>12         /// <returns></returns>13         private static bool IsMessyCode(string txt)14         {15             var bytes = Encoding.UTF8.GetBytes(txt);16             for (var i = 0; i < bytes.Length; i++)17             {18                 if (i < bytes.Length - 3)19                     if (bytes[i] == 239 && bytes[i + 1] == 191 && bytes[i + 2] == 189)20                     {21                         return true;22                     }23             }24             return false;25         }26 27         /// <summary>28         /// 将Html字符串 输出到PDF档里29         /// </summary>30         /// <param name="htmlText"></param>31         /// <returns></returns>32         public static byte[] ConvertHtmlTextToPdf(string htmlText)33         {34             return ConvertHtmlTextToPdf(htmlText, "", 0, 0, 0, 0);35         }36 37         /// <summary>38         /// 将Html字符串 输出到PDF档里,并添加水印39         /// </summary>40         /// <param name="htmlText">网页代码</param>41         /// <param name="picPath">水印路径</param>42         /// <param name="left">距离左边距离</param>43         /// <param name="top">距顶部距离</param>44         /// <param name="width">水印宽度</param>45         /// <param name="height">水印高度</param>46         /// <returns></returns>47         public static byte[] ConvertHtmlTextToPdf(string htmlText, string picPath, int left, int top, int width, int height)48         {49             if (string.IsNullOrEmpty(htmlText))50             {51                 return null;52             }53             //避免当htmlText无任何html tag标签的纯文字时，转PDF时会挂掉，所以一律加上<p>标签54             htmlText = "<p>" + htmlText + "</p>";55             MemoryStream outputStream = new MemoryStream();//要把PDF写到哪个串流56             byte[] data = Encoding.UTF8.GetBytes(htmlText);//字串转成byte[]57             MemoryStream msInput = new MemoryStream(data);58             Document doc = new Document();//要写PDF的文件，建构子没填的话预设直式A459             PdfWriter writer = PdfWriter.GetInstance(doc, outputStream);60             //指定文件预设开档时的缩放为100%61             PdfDestination pdfDest = new PdfDestination(PdfDestination.XYZ, 0, doc.PageSize.Height, 1f);62             //开启Document文件 63             doc.Open();64 65             //写入水印图片66             if (!string.IsNullOrEmpty(picPath))67             {68                 Image img = Image.GetInstance(picPath);69                 //设置图片的位置70                 img.SetAbsolutePosition(width + left, (doc.PageSize.Height - height) - top);71                 //设置图片的大小72                 img.ScaleAbsolute(width, height);73                 doc.Add(img);74             }75             try76             {77                 //使用XMLWorkerHelper把Html parse到PDF档里79                 XMLWorkerHelper.GetInstance().ParseXHtml(writer, doc, msInput, null, Encoding.UTF8);80                 //将pdfDest设定的资料写到PDF档81                 PdfAction action = PdfAction.GotoLocalPage(1, pdfDest, writer);82                 writer.SetOpenAction(action);83             }84             catch (Exception)85             {86                 return null;87             }88             doc.Close();89             msInput.Close();90             outputStream.Close();91             //回传PDF档案 92             return outputStream.ToArray();94         }95 96         #endregion97 98     }

  4、获取网页字符串的方法

1         /// <summary> 2         /// 获取网站内容，包含了 HTML+CSS+JS 3         /// </summary> 4         /// <returns>String返回网页信息</returns> 5         public static string GetWebContent(string inpath) 6         { 7             try 8             { 9                 WebClient myWebClient = new WebClient();10                 //获取或设置用于向Internet资源的请求进行身份验证的网络凭据11                 myWebClient.Credentials = CredentialCache.DefaultCredentials;12                 //从指定网站下载数据13                 Byte[] pageData = myWebClient.DownloadData(inpath);14                 //如果获取网站页面采用的是GB2312，则使用这句15                 string pageHtml = Encoding.UTF8.GetString(pageData);16                 bool isBool = IsMessyCode(pageHtml);//判断使用哪种编码 读取网页信息17                 if (!isBool)18                 {19                     string pageHtml1 = Encoding.UTF8.GetString(pageData);20                     pageHtml = pageHtml1;21                 }22                 else23                 {24                     string pageHtml2 = Encoding.Default.GetString(pageData);25                     pageHtml = pageHtml2;26                 }27                 return pageHtml;28             }29             catch (WebException webEx)30             {31                 return webEx.Message;32             }33         }

  5、MVC设计模式下获取控制器视图Html方法，很XX的一个问题就是只能获取调用此方法的控制器下所有视图，不能跨控制器获取视图，有待优化

1         /// <summary> 2         /// 获取MVC视图Html 3         /// </summary> 4         /// <param name="context">控制器上下文</param> 5         /// <param name="viewName">视图名称</param> 6         /// <param name="param"></param> 7         /// <returns></returns> 8         public static string GetViewHtml(ControllerContext context, string viewName) 9         {10             if (string.IsNullOrEmpty(viewName))11                 viewName = context.RouteData.GetRequiredString("action");12             using (var sw = new StringWriter())13             {14                 ViewEngineResult viewResult = ViewEngines.Engines.FindPartialView(context, viewName);15                 var viewContext = new ViewContext(context, viewResult.View, context.Controller.ViewData, context.Controller.TempData, sw);16                 try17                 {18                     viewResult.View.Render(viewContext, sw);19                 }20                 catch (Exception ex)21                 {22                     throw;23                 }24 25                 return sw.GetStringBuilder().ToString();26             }27         }

  6、将pdf流输出至客户浏览器下载方法

1         /// <summary> 2         /// 将pdf文件流输出至浏览器下载 3         /// </summary> 4         /// <param name="pdfFile">PDF文件流</param> 5         public static void PdfDownload(byte[] pdfFile) 6         { 7             byte[] buffer = pdfFile; 8             Stream iStream = new MemoryStream(buffer); 9             try10             {11                 int length;12                 long dataToRead;13                 string filename = DateTime.Now.ToString("yyyyMMddHHmmss") + ".pdf";//保存的文件名称14                 dataToRead = iStream.Length;15                 HttpContext.Current.Response.Clear();16                 HttpContext.Current.Response.ClearHeaders();17                 HttpContext.Current.Response.ClearContent();18                 HttpContext.Current.Response.ContentType = "application/pdf"; //文件类型 19                 HttpContext.Current.Response.AddHeader("Content-Length", dataToRead.ToString());//添加文件长度，进而显示进度 20                 HttpContext.Current.Response.AddHeader("Content-Disposition", "attachment; filename=" + HttpUtility.UrlEncode(filename, Encoding.UTF8));21                 while (dataToRead > 0)22                 {23                     if (HttpContext.Current.Response.IsClientConnected)24                     {25                         length = buffer.Length;26                         HttpContext.Current.Response.OutputStream.Write(buffer, 0, length);27                         HttpContext.Current.Response.Flush();28                         buffer = new Byte[length];29                         dataToRead = dataToRead - length;30                     }31                     else32                     {33                         dataToRead = -1;34                     }35                 }36             }37             catch (Exception ex)38             {39                 HttpContext.Current.Response.Write("文件下载时出现错误!");40             }41             finally42             {43                 if (iStream != null)44                 {45                     iStream.Close();46                 }47                 //结束响应，否则将导致网页内容被输出到文件，进而文件无法打开  48                 HttpContext.Current.Response.Flush();49                 HttpContext.Current.Response.End();50 51             }52         }

  7、MVC控制器下调用Demo|步骤4、6 方法封装至帮助类）

1     public class HomeController : Controller 2     { 3         // 4         // GET: /Home/ 5  6         public ActionResult Index() 7         { 8             //从网址下载Html字符串(方法一) 9             string inpath = System.Web.HttpContext.Current.Server.MapPath("~/PDFTemplate/test.html");10             string htmlText = HtmlToPdfHelper.GetWebContent(inpath);//此处调用步骤4方法11 12             //获取MVC视图Html字符串(方法二)13             //string htmlText = GetViewHtml(ControllerContext, "Test");//此处调用步骤5方法14 15             //水印图片路径16             string picPath = Server.MapPath("~/PDFTemplate/TemplateImg/authentication-iocn.webp");17             //html转pdf并加上水印18             byte[] pdfFile = HtmlToPdfHelper.ConvertHtmlTextToPdf(htmlText, picPath, 100, 200, 100, 100);19             //输出至客户端20             HtmlToPdfHelper.PdfDownload(pdfFile);//此处调用步骤6方法21 22             return View();23         }24 25         public ActionResult Test()26         {27             return View();28         }29 30         /// <summary>31         /// 获取MVC视图Html32         /// </summary>33         /// <param name="context"></param>34         /// <param name="viewName">视图名称</param>35         /// <returns></returns>36         public static string GetViewHtml(ControllerContext context, string viewName)37         {38             if (string.IsNullOrEmpty(viewName))39                 viewName = context.RouteData.GetRequiredString("action");40             using (var sw = new StringWriter())41             {42                 ViewEngineResult viewResult = ViewEngines.Engines.FindPartialView(context, viewName);43                 var viewContext = new ViewContext(context, viewResult.View, context.Controller.ViewData,44                     context.Controller.TempData, sw);45                 try46                 {47                     viewResult.View.Render(viewContext, sw);48                 }49                 catch (Exception ex)50                 {51                     throw;52                 }53 54                 return sw.GetStringBuilder().ToString();55             }56         }57     }

  总结：我理解的解决思路是将html读取转换成字符串，之后再通过 itextsharp 转换成 pdf 比特币 传输至客户端或直接保存至服务器生成链接供用户下载。（新手上路，不妥之处，欢迎各位大神指教）

  以上代码仅满足个人业务逻辑需求，谢谢浏览。