In this article I will explain with an example, how to send email using
MailKit library in ASP.Net Core MVC (.Net Core).
Installing MailKit package
Mail Server Settings in AppSettings.json file
The Mail Server settings are saved in the SMTP section as shown below.
{
"Smtp": {
"Server": "smtp.gmail.com",
"Port": 587
}
}
MimeKit MimeMessage and MailKit SmtpClient class
MimeMessage class properties
Following are the required properties of the MimeMessage class.
From – Sender’s email address.
To – Recipient(s) Email Address.
CC – Carbon Copies. (If any)
BCC – Blind Carbon Copies. (If any)
Subject – Subject of the Email.
Body – Body of the Email.
Attachments – Attachments. (If any)
ReplyTo – ReplyTo Email address.
SmtpClient class methods
Following are the methods of the SmtpClient class.
Connect – The connection to the SMTP Server is established using the domain and the port number.
Authenticate – The username and password of the SMTP Server is authenticated.
Send – The MimeMessage object is passed to it and the email is sent.
Disconnect – Disconnects the connection with SMTP Server.
Model
The Model class consists of following properties.
public class EmailModel
{
public string To { get; set; }
public string Subject { get; set; }
public string Body { get; set; }
public string Email { get; set; }
public string Password { get; set; }
}
Namespaces
You will need to import the following namespaces.
using MimeKit;
using MailKit.Net.Smtp;
using MailKit.Security;
Controller
The Controller consists of following Action methods.
Action method for handling GET operation
Inside this Action method, simply the View is returned.
Action method for handling POST operation
This Action method handles the call made from the POST function from the View which accepts EmailModel class object as a parameter.
Inside this Action method, the posted values are captured through the EmailModel class object. All the fetched values are set into an object of the MimeMessage class except the Body.
Setting Body of Email
For Body, an object of Builder class is created. The Body of the email is Text (Non HTML) hence it is set into the TextBody property of the Builder class object.
Sending Email
Then, an object of the SmtpClient class is created and the values of Host and Port are fetched from the SMTP section of the AppSettings.json file and are passed as parameter to the Connect method along with the SecureSocketOptions set to Auto.
Note: Setting
Auto allows
MailKit service to decide which
SSL or
TLS option to use. Hence, enabling
SSL is not required.
Also, the CheckCertificateRevocation is set to FALSE.
Note: This is optional and must be used only when Certificate errors are occurring.
Finally, the methods of Mail Server such as
Connect,
Authenticate,
Send and
Disconnect are executed and a success message is set into the
ViewBag object and the View is returned.
public class HomeController : Controller
{
public IConfiguration Configuration { get; set; }
public HomeController(IConfiguration _configuration)
{
this.Configuration = _configuration;
}
public IActionResult Index()
{
return View();
}
[HttpPost]
public IActionResult Index(EmailModel model)
{
//Read SMTP section from AppSettings.json.
string host = this.Configuration.GetValue<string>("Smtp:Server");
int port = this.Configuration.GetValue<int>("Smtp:Port");
using (MimeMessage mm = new MimeMessage())
{
mm.From.Add(new MailboxAddress("Sender", model.Email));
mm.To.Add(new MailboxAddress("Recipient", model.To));
mm.Subject = model.Subject;
BodyBuilder builder = new BodyBuilder()
{
TextBody = model.Body
};
mm.Body = builder.ToMessageBody();
using (SmtpClient smtp = new SmtpClient())
{
//Set to False to avoid Certificate verification.
smtp.CheckCertificateRevocation = false;
smtp.Connect(host, port, SecureSocketOptions.Auto);
smtp.Authenticate(model.Email, model.Password);
smtp.Send(mm);
smtp.Disconnect(true);
}
}
ViewBag.Message = "Email Sent.";
return View();
}
}
View
HTML Markup
Inside the View, the EmailModel class is declared as model for the View and ASP.Net TagHelpers is inherited.
The View consists of an HTML Form which has been created using the following TagHelpers attributes.
asp-action – Name of the Action. In this case the name is Index.
asp-controller – Name of the Controller. In this case the name is Home.
method – It specifies the Form Method i.e. GET or POST. In this case it will be set to POST.
The Form consists of HTML TextBoxes, TextArea element and a Submit Button.
Submitting the Form
When the Send Button is clicked, the Form gets submitted and the Model object is sent to the Controller.
Finally, the
ViewBag object is checked for NULL and if it is not NULL then, the value of the object is displayed using
JavaScript Alert
MessageBox.
@addTagHelper*, Microsoft.AspNetCore.Mvc.TagHelpers
@model Send_Email_MailKit_Core_MVC.Models.EmailModel
@{
Layout = null;
}
<!DOCTYPE html>
<html>
<head>
<meta name="viewport"content="width=device-width" />
<title>Index</title>
</head>
<body>
<form method="post" asp-controller="Home" asp-action="Index">
<table>
<tr>
<td style="width: 80px">To:</td>
<td><input type="text" asp-for="To" /></td>
</tr>
<tr><td> </td></tr>
<tr>
<td>Subject:</td>
<td><input type="text" asp-for="Subject" /></td>
</tr>
<tr><td> </td></tr>
<tr>
<td valign="top">Body:</td>
<td><textarea cols="20" rows="3" asp-for="Body"></textarea></td>
</tr>
<tr><td> </td></tr>
<tr>
<td>Gmail Email:</td>
<td><input type="text" asp-for="Email" /></td>
</tr>
<tr><td> </td></tr>
<tr>
<td>Gmail Password:</td>
<td><input type="password" asp-for="Password" /></td>
</tr>
<tr><td> </td></tr>
<tr>
<td></td>
<td><input type="submit" value="Send" /></td>
</tr>
</table>
</form>
@if (ViewBag.Message != null)
{
<script type="text/javascript">
window.onload = function () {
alert("@ViewBag.Message");
};
</script>
}
</body>
</html>
Possible Errors
The possible errors (exceptions) occurring while sending email with
MailKit in .Net are covered in the following article.
Screenshots
Email Form
![ASP.Net Core: Send Email using MailKit]()
Received Email
![ASP.Net Core: Send Email using MailKit]()
Downloads
