How to send emails in .NET part 7: adding style to HTML contents
September 2, 2014 12 Comments
In this post we saw how to build a simple HTML email with no styling. It looked a bit bleak so we’ll “dress it up” a little.
You cannot simply add a reference to an external CSS file like you would on a normal HTML web page. External references are ignored in the email body as they can can contain malicious material and code.
You can place CSS code directly in the HTML code in the following ways:
- Using the style tag within the head section
- Using the style attribute on individual elements
- Using old-style attributes, such as cellspacing, border, width etc. on individual elements
All of these should be familiar from general web UI programming. Here’s an example of an embedded style tag in the head section:
string from = "andras.nemes@company.com";
string to = "john.smith@company.com";
string subject = "Testing html body";
string htmlBody = @"
<html lang=""en"">
<head>
<meta content=""text/html; charset=utf-8"" http-equiv=""Content-Type"">
<title>
Upcoming topics
</title>
<style type=""text/css"">
HTML{background-color: #e8e8e8;}
.courses-table{font-size: 12px; padding: 3px; border-collapse: collapse; border-spacing: 0;}
.courses-table .description{color: #505050;}
.courses-table td{border: 1px solid #D1D1D1; background-color: #F3F3F3; padding: 0 10px;}
.courses-table th{border: 1px solid #424242; color: #FFFFFF;text-align: left; padding: 0 10px;}
.green{background-color: #6B9852;}
</style>
</head>
<body>
<table class=""courses-table"">
<thead>
<tr>
<th class=""green"">Topic</th>
<th class=""green"">Est. # of posts</th>
</tr>
</thead>
<tbody>
<tr>
<td class=""description"">Using a Windows service in your project</td>
<td>5</td>
</tr>
<tr>
<td class=""description"">More RabbitMQ in .NET</td>
<td>5</td>
</tr>
</tbody>
</table>
</body>
</html>
";
MailMessage mailMessage = new MailMessage(from, to, subject, htmlBody);
mailMessage.IsBodyHtml = true;
string smtpServer = "mail.company.com";
SmtpClient client = new SmtpClient(smtpServer);
client.Send(mailMessage);
The above message is rendered as follows in my MS outlook client:
It’s still not very corporate looking but now you at least know how to add styles to a HTML message in .NET.
Keep in mind that email clients are not as up-to-date with CSS code as modern web browsers, so not everything will work in an email.
Read all posts related to emailing in .NET here.
About Andras Nemes
Exercises in .NET with Andras Nemes 
nice post..
Very helpful. But I need to insert a variable.
How to insert a variable instead of “More RabbitMQ in .NET”?
string.Format is a good option. //Andras
Can you post some example? I need input variable instead “More RabbitMQ in .NET”..pls help
Does not works, shows as plain text.
what email service have you tested? Does it support HTML? The code does indeed work, we use it in production. //Andras
Can you think of a reason why this might result in a blank email in Outlook?
When I view source and then use the content to create an html page, it looks right, but the email comes through blank
Works very well. I believe he was saying it just shows text when he try’s to make his variable fit into the html. Probably just misformatting
Very Help Full,It Will Work Will Be Fine
thank you this worked perfect!
Its very help full,thank you so much sir.
nice post ,
In this example, how do I add razor variables in the table. @
detects it as text