How to convert RTF to HTML email with embedded images and send it via SmtpClient in .NET C#
In this article you will find how to create a simple .NET/C# application which converts RTF document to HTML email with embedded images and sends it using MS Outlook programmatically.
Let’s make a C# code satisfying of these conditions:
- Acceptable for any .NET application: ASP.NET, Windows Forms, WPF, Console, Web Service, SilverLight etc.
- Works at 32-bit and 64-bit Windows machines.
- Compatible with .NET 2.0, 3.5 , 4.0, 4.5 frameworks and even higher if such will appear.
To make converting of RTF to HTML email with images at server-side we’ll use RTF-to-HTML DLL .Net library. It’s .Net component which will provides API to convert RTF to HTML with all images which we’ll get in a list after converting. We need these images extracted from RTF to further adding them into email as attachments.
To get the ball rolling, download the RTF-to-HTML DLL .Net component from here: Скачать.
To check this out first hand, unpack the archive and create a new C# Console Application named SmtpRtfToHtml. Next add reference to the “SautinSoft.RtfToHtml.dll” as shown on picture below:
How to add a reference to SautinSoft.RtfToHtml.dll
This is C# code of our application:
using System;
using System;
using System.IO;
using System.Net;
using System.Net.Mail;
using System.Drawing;
using System.Collections;
namespace Sample
{
class Program
{
static void Main(string[] args)
{
string pathToRtf = @"c:\Document.rtf";
// 1. Convert RTF to HTML and place all images to list
string rtf = File.ReadAllText(pathToRtf);
SautinSoft.RtfToHtml r = new SautinSoft.RtfToHtml();
r.ImageStyle.IncludeImageInHtml = false;
ArrayList imageList = new ArrayList();
// 2. After launching this method we'll get our RTF document in HTML format
// and list of all images.
string html = r.ConvertString(rtf, imageList);
// 3. Create HTML email
string from = "bob@bobsite.com";
string to = "john@johnsite.com";
string subject = "This is a testing email from Bob to John using SmtpClient";
MailMessage emailMessage = new MailMessage();
emailMessage.From = new MailAddress(from);
emailMessage.To.Add(to);
emailMessage.Subject = subject.Replace("\r\n", "");
// 4. Attach images to email
System.Net.Mail.AlternateView altView = AlternateView.CreateAlternateViewFromString(html, null, "text/html");
foreach (SautinSoft.RtfToHtml.SautinImage simg in imageList)
{
if (simg.Img != null)
{
LinkedResource lr = null;
System.IO.MemoryStream ms = new System.IO.MemoryStream();
simg.Img.Save(ms, System.Drawing.Imaging.ImageFormat.Png);
if (ms != null && ms.Position > 0)
ms.Position = 0;
lr = new LinkedResource(ms);
lr.ContentId = simg.Cid.Replace("cid:", "");
altView.LinkedResources.Add(lr);
}
}
emailMessage.AlternateViews.Add(altView);
// 5. Send the message using email account
string userName = "bobuser";
string userPassword = "bobpassword";
SmtpClient client = new SmtpClient();
client.Port = 25;
client.DeliveryMethod = SmtpDeliveryMethod.Network;
//client.UseDefaultCredentials = false;
// Some smtp servers doesn't require credentials, therefore
// you may set: client.UseDefaultCredentials = false;
// and remove the line: client.Credentials = new NetworkCredential(userName, userPassword);
client.Credentials = new NetworkCredential(userName, userPassword);
client.Host = "smtpout.bobsite.com";
client.Send(emailMessage);
}
}
}
Если вам нужен пример кода или у вас есть вопрос: напишите нам по адресу support@sautinsoft.ru или спросите в онлайн-чате (правый нижний угол этой страницы) или используйте форму ниже: