1、安裝Nuget包MailKit，引用命名空間。
using MailKit.Net.Smtp; using MimeKit;
注意：引用MailKit對應(yīng)最新版本
2、定義收發(fā)地址和標題
MimeMessage message = new MimeMessage(); MailboxAddress from = new MailboxAddress("Admin","admin@example.com"); message.From.Add(from); MailboxAddress to = new MailboxAddress("User", "user@example.com"); message.To.Add(to); message.Subject = "This is email subject";
注意：Admin,User分別對應(yīng)發(fā)送接收郵箱前綴
3、編寫內(nèi)容
BodyBuilder bodyBuilder = new BodyBuilder(); bodyBuilder.HtmlBody = "<h1>Hello World!</h1>"; bodyBuilder.TextBody = "Hello World!";
message.Body = bodyBuilder.ToMessageBody();
注意：也可以自定義模板，插入圖片等等。
4、連接SMTP服務(wù)器發(fā)送郵件
SmtpClient client = new SmtpClient();
client.Connect("smtp_address_here", port_here, true); //例如：smtp.exmail.qq.com，465
client.Authenticate("admin@example.com", "password")； //發(fā)送郵件的賬戶密碼
client.Send(message);
client.Disconnect(true);
client.Dispose();
