c#asp.net asp.net-core email asp.net-web-api

c# asp.net Send email template html

I have an asp.net web app to send emails, and I have tried to send an html file template. I can send my file, but the images from the template dont load on the message sent!

public void SendEmail(string EmailAddress)    
{

      try
        {

            MailMessage mail = new MailMessage();
            mail.To.Add(EmailAddress);
            mail.From = new MailAddress("[email protected]");
            mail.Subject = txtSubject.Text;
            
            string FilePath = Server.MapPath("templateHtml.html");
            StreamReader str = new StreamReader(FilePath);
            string body = str.ReadToEnd();
            //string body = Server.HtmlEncode(str.ReadToEnd());

            mail.IsBodyHtml = true;
            mail.Body = body;
            SmtpClient smtp = new SmtpClient();
            smtp.Host = smtpClient;
            smtp.Credentials = new NetworkCredential(email, password);
            
            smtp.EnableSsl = true;
            smtp.Send(mail);
            str.Close();
            Response.Write("ok!")
        }
    catch
        {                
            Response.Write("so bad");                               
        }

 }

...

My htmltemplate is like:

    <!DOCTYPE html>
    <html>
    <head>
    <meta charset="utf-8" />
    <title></title>
    </head>
    <body>

    <br />
    <p>This is an image</p>
    <img src="Images/image1.jpg">

    <p>This is an image</p>
    <img src="http://localhost:1114/WebBody/Images/image2.jpg">

    <p>image from net</p>
    <img src="https://cdn.mos.cms.futurecdn.net/FVqUjfbiHS9imyJiRiM53-970-80.jpg.webp" width="40%">

    </body>
    </html>

... When I send this html file, just the last image is loaded.

Any ideas?

Solution

There are two ways, one is to upload the image to the server to make it public, the other is to encode the image to base64.

I will show the second method here.

First, Choose a transcoding website(website), Encoding the image to base64.

Second, Use:

<img src='data:image/jpeg;base64,  <!-- Base64 data --> />

in your template html.

Then the image will load in email.