(C#) Add Image to HTML Email

See more Email Object Examples

Demonstrates how to add an image to an HTML email.

Chilkat .NET Downloads

Chilkat .NET Framework

Chilkat for .NET Core

// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

Chilkat.Email email = new Chilkat.Email();
bool success;

email.From = "Matt <matt@example.com>";
email.AddTo("Joe","joe@example.com");
email.Subject = "This is a test";

// Add an HTML body with an image tag.
string html = "<html><body><p>Test with image:</p><p><img src=\"/wildlife/starfish.jpg\" /></p></body></html>";
email.SetHtmlBody(html);

// Add the image data from a file.  The pathInHtml must match the value of the img tag's src attribute.
string pathInHtml = "/wildlife/starfish.jpg";
// The actual path of the JPG file in the local filesystem:
string pathOnDisk = "qa_data/jpg/starfish20.jpg";

success = email.AddRelatedFile2(pathOnDisk,pathInHtml);
if (success == false) {
    Debug.WriteLine(email.LastErrorText);
    return;
}

// The email is now properly constructed with an image that will be visible in the HTML.
// In this example, we'll save it to a .eml file and verify by loading the .eml in an email client such as Mozilla Thunderbird.

success = email.SaveEml("qa_output/starfish.eml");

// Also, we can examine the MIME to understand how the image data in the MIME is associated with the img tag in the HTML.
// It is the Content-Location header value that must match the value of the img tag's src attribute.

Debug.WriteLine(email.GetMime());

// Here's the MIME:

// MIME-Version: 1.0
// Date: Thu, 26 May 2022 11:09:12 -0500
// Message-ID: <B1D499F74F533E287BFE04BBD79AAF1D973B61E3@SLICE>
// Content-Type: multipart/related; boundary="------------000205040704010904010706"
// X-Priority: 3 (Normal)
// From: Matt <matt@example.com>
// CKX-Bounce-Address: matt@example.com
// To: Joe <joe@example.com>
// Subject: This is a test
// 
// --------------000205040704010904010706
// Content-Type: text/html; charset=us-ascii
// Content-Transfer-Encoding: 7bit
// 
// <html><body><p>Test with image:</p><p><img src="/wildlife/starfish.jpg" /></p></body></html>
// --------------000205040704010904010706
// Content-Type: image/jpeg; name="/wildlife/starfish.jpg"
// Content-Transfer-Encoding: base64
// Content-Disposition: inline; filename="/wildlife/starfish.jpg"
// Content-Location: /wildlife/starfish.jpg
// 
// /9j/4AAQSkZJRgABAQEASABIAAD//gAmRmlsZSB3cml0dGVuIGJ5IEFkb2JlIFBob3Rvc2hvcD8g
// NC4w/9sAQwAQCwwODAoQDg0OEhEQExgoGhgWFhgxIyUdKDozPTw5Mzg3QEhcTkBEV0U3OFBtUVdf
// YmdoZz5NcXlwZHhcZWdj/9sAQwEREhIYFRgvGhovY0I4QmNjY2NjY2NjY2NjY2NjY2NjY2NjY2Nj
// Y2NjY2NjY2NjY2NjY2NjY2NjY2NjY2NjY2Nj/8IAEQgAFAAUAwERAAIRAQMRAf/EABcAAAMBAAAA
// AAAAAAAAAAAAAAIDBAX/xAAYAQADAQEAAAAAAAAAAAAAAAABAgMEAP/aAAwDAQACEAMQAAAB2kZY
// NNEijWKddfTmLgALWH//xAAbEAACAgMBAAAAAAAAAAAAAAABAgMRAAQSE//aAAgBAQABBQL0XqN+
// pM2aqJGMiqFFCyg7z//EABwRAAICAgMAAAAAAAAAAAAAAAERAAIQIQMSUf/aAAgBAwEBPwHqU5aq
// Axx+y1tMQl4elj//xAAcEQEAAQUBAQAAAAAAAAAAAAABEQACEBIhA1H/2gAIAQIBAT8B3Bhqy7Zc
// enyiwmGgDhiOzj//xAAdEAABAwUBAAAAAAAAAAAAAAABAAIREBIhIkFR/9oACAEBAAY/ArZyn+Cg
// xtxWuJaoCnqDuin/xAAcEAABBAMBAAAAAAAAAAAAAAABABEhYRAxQVH/2gAIAQEAAT8hkEwPUUR9
// DYfE4nxtRpIkBTsayuALIiuY/9oADAMBAAIAAwAAABDWPTsf/8QAGhEAAwADAQAAAAAAAAAAAAAA
// AAEREDFBIf/aAAgBAwEBPxC0DVPcWm+Ce4OesrkE6bjH/8QAGBEBAQEBAQAAAAAAAAAAAAAAAREA
// QRD/2gAIAQIBAT8QahMiOc8YgSrnTY3ELclHXn//xAAcEAEBAAIDAQEAAAAAAAAAAAABEQAhMUFx
// EFH/2gAIAQEAAT8Qn3igmSZSj+c4N4zapMy9IjFV98wncN2iuLFsCEbDGxQkI6RO/n//2Q==
// 
// --------------000205040704010904010706--