Sendgrid Web API V3

with SENDGRID API easily integrate to ensure your most important email reach your inbox, Now this blog explains how to use sendgrid web api v3. This API is RESTful, fully featured, easy to integrate with and offers support in 7 different languages(C#,Java,Go,NodeJs,Php,Python and Ruby). 

Prerequisites:

.Net Version 4.5.2

Sendgrid Service

Upgrade the development environment with sendgrid API

Install Package:

To use sendgrid in your c# Project  download the SendGrid C# .NET libraries directly from our Github repository, If you have the Nuget package manager installed, you can grab automatically by using 

PM> Install-Package SendGrid

Once you have the SendGrid libraries properly referenced in your project, you can include calls to them in your code. For a sample implementation, check the Example folder.

Add the following namespaces to use the library:

using System;
using System.Web.Script.Serialization;
using SendGrid;
using SendGrid.Helpers.Mail; // Include if you want to use the Mail Helper

Here is the simple example using Mail Helper Class

using System;
using SendGrid;
using SendGrid.Helpers.Mail;
using System.Threading.Tasks;

namespace Example
{
    internal class Example
    {
        private static void Main()
        {
            Execute().Wait();
        }

        static async Task Execute()
        {
            string apiKey = Environment.GetEnvironmentVariable("NAME_OF_THE_ENVIRONMENT_VARIABLE_FOR_YOUR_SENDGRID_KEY", EnvironmentVariableTarget.User);
            dynamic sg = new SendGridAPIClient(apiKey);

            Email from = new Email("test@example.com");
            string subject = "Hello World from the SendGrid CSharp Library!";
            Email to = new Email("test@example.com");
            Content content = new Content("text/plain", "Hello, Email!");
            Mail mail = new Mail(from, subject, to, content);

            dynamic response = await sg.client.mail.send.post(requestBody: mail.Get());
        }
    }
}
This example shows you some more concepts of sendgrid and implementation
 private static async Task KitchenSink()
        {

            String apiKey = Environment.GetEnvironmentVariable("SENDGRID_APIKEY", EnvironmentVariableTarget.User);
            dynamic sg = new SendGrid.SendGridAPIClient(apiKey, "https://api.sendgrid.com");

            Mail mail = new Mail();

            Email email = new Email();
            email.Name = "Example User";
            email.Address = "test@example.com";
            mail.From = email;

            mail.Subject = "Hello World from the SendGrid CSharp Library";

            Personalization personalization = new Personalization();
            email = new Email();
            email.Name = "Example User";
            email.Address = "test1@example.com";
            personalization.AddTo(email);
            email = new Email();
            email.Name = "Example User";
            email.Address = "test2@example.com";
            personalization.AddCc(email);
            email = new Email();
            email.Name = "Example User";
            email.Address = "test3@example.com";
            personalization.AddCc(email);
            email = new Email();
            email.Name = "Example User";
            email.Address = "test4@example.com";
            personalization.AddBcc(email);
            email = new Email();
            email.Name = "Example User";
            email.Address = "test5@example.com";
            personalization.AddBcc(email);
            personalization.Subject = "Thank you for signing up, %name%";
            personalization.AddHeader("X-Test", "True");
            personalization.AddHeader("X-Mock", "True");
            personalization.AddSubstitution("%name%", "Example User");
            personalization.AddSubstitution("%city%", "Denver");
            personalization.AddCustomArgs("marketing", "false");
            personalization.AddCustomArgs("transactional", "true");
            personalization.SendAt = 1461775051;
            mail.AddPersonalization(personalization);

            personalization = new Personalization();
            email = new Email();
            email.Name = "Example User";
            email.Address = "test1@example.com";
            personalization.AddTo(email);
            email = new Email();
            email.Name = "Example User";
            email.Address = "test2@example.com";
            personalization.AddCc(email);
            email = new Email();
            email.Name = "Example User";
            email.Address = "test3@example.com";
            personalization.AddCc(email);
            email = new Email();
            email.Name = "Example User";
            email.Address = "test4@example.com";
            personalization.AddBcc(email);
            email = new Email();
            email.Name = "Example User";
            email.Address = "test5@example.com";
            personalization.AddBcc(email);
            personalization.Subject = "Thank you for signing up, %name%";
            personalization.AddHeader("X-Test", "True");
            personalization.AddHeader("X-Mock", "True");
            personalization.AddSubstitution("%name%", "Example User");
            personalization.AddSubstitution("%city%", "Denver");
            personalization.AddCustomArgs("marketing", "false");
            personalization.AddCustomArgs("transactional", "true");
            personalization.SendAt = 1461775051;
            mail.AddPersonalization(personalization);

            Content content = new Content();
            content.Type = "text/plain";
            content.Value = "Textual content";
            mail.AddContent(content);
            content = new Content();
            content.Type = "text/html";
            content.Value = "<html><body>HTML content</body></html>";
            mail.AddContent(content);
            content = new Content();
            content.Type = "text/calendar";
            content.Value = "Party Time!!";
            mail.AddContent(content);

            Attachment attachment = new Attachment();
            attachment.Content = "TG9yZW0gaXBzdW0gZG9sb3Igc2l0IGFtZXQsIGNvbnNlY3RldHVyIGFkaXBpc2NpbmcgZWxpdC4gQ3JhcyBwdW12";
            attachment.Type = "application/pdf";
            attachment.Filename = "balance_001.pdf";
            attachment.Disposition = "attachment";
            attachment.ContentId = "Balance Sheet";
            mail.AddAttachment(attachment);

            attachment = new Attachment();
            attachment.Content = "BwdW";
            attachment.Type = "image/png";
            attachment.Filename = "banner.png";
            attachment.Disposition = "inline";
            attachment.ContentId = "Banner";
            mail.AddAttachment(attachment);

            mail.TemplateId = "13b8f94f-bcae-4ec6-b752-70d6cb59f932";

            mail.AddHeader("X-Day", "Monday");
            mail.AddHeader("X-Month", "January");

            mail.AddSection("%section1", "Substitution for Section 1 Tag");
            mail.AddSection("%section2", "Substitution for Section 2 Tag");

            mail.AddCategory("customer");
            mail.AddCategory("vip");

            mail.AddCustomArgs("campaign", "welcome");
            mail.AddCustomArgs("sequence", "2");

            ASM asm = new ASM();
            asm.GroupId = 3;
            List<int> groups_to_display = new List<int>()
            {
                1, 4, 5
            };
            asm.GroupsToDisplay = groups_to_display;
            mail.Asm = asm;

            mail.SendAt = 1461775051;

            mail.SetIpPoolId = "23";

            // This must be a valid [batch ID](https://sendgrid.com/docs/API_Reference/SMTP_API/scheduling_parameters.html)
            // mail.BatchId = "some_batch_id";

            MailSettings mailSettings = new MailSettings();
            BCCSettings bccSettings = new BCCSettings();
            bccSettings.Enable = true;
            bccSettings.Email = "test@example.com";
            mailSettings.BccSettings = bccSettings;
            BypassListManagement bypassListManagement = new BypassListManagement();
            bypassListManagement.Enable = true;
            mailSettings.BypassListManagement = bypassListManagement;
            FooterSettings footerSettings = new FooterSettings();
            footerSettings.Enable = true;
            footerSettings.Text = "Some Footer Text";
            footerSettings.Html = "<bold>Some HTML Here</bold>";
            mailSettings.FooterSettings = footerSettings;
            SandboxMode sandboxMode = new SandboxMode();
            sandboxMode.Enable = true;
            mailSettings.SandboxMode = sandboxMode;
            SpamCheck spamCheck = new SpamCheck();
            spamCheck.Enable = true;
            spamCheck.Threshold = 1;
            spamCheck.PostToUrl = "https://gotchya.example.com";
            mailSettings.SpamCheck = spamCheck;
            mail.MailSettings = mailSettings;

            TrackingSettings trackingSettings = new TrackingSettings();
            ClickTracking clickTracking = new ClickTracking();
            clickTracking.Enable = true;
            clickTracking.EnableText = false;
            trackingSettings.ClickTracking = clickTracking;
            OpenTracking openTracking = new OpenTracking();
            openTracking.Enable = true;
            openTracking.SubstitutionTag = "Optional tag to replace with the open image in the body of the message";
            trackingSettings.OpenTracking = openTracking;
            SubscriptionTracking subscriptionTracking = new SubscriptionTracking();
            subscriptionTracking.Enable = true;
            subscriptionTracking.Text = "text to insert into the text/plain portion of the message";
            subscriptionTracking.Html = "<bold>HTML to insert into the text/html portion of the message</bold>";
            subscriptionTracking.SubstitutionTag = "text to insert into the text/plain portion of the message";
            trackingSettings.SubscriptionTracking = subscriptionTracking;
            Ganalytics ganalytics = new Ganalytics();
            ganalytics.Enable = true;
            ganalytics.UtmCampaign = "some campaign";
            ganalytics.UtmContent = "some content";
            ganalytics.UtmMedium = "some medium";
            ganalytics.UtmSource = "some source";
            ganalytics.UtmTerm = "some term";
            trackingSettings.Ganalytics = ganalytics;
            mail.TrackingSettings = trackingSettings;

            email = new Email();
            email.Address = "test@example.com";
            mail.ReplyTo = email;

            dynamic response = await sg.client.mail.send.post(requestBody: mail.Get());
            Console.WriteLine(response.StatusCode);
            Console.WriteLine(response.Body.ReadAsStringAsync().Result);
            Console.WriteLine(response.Headers.ToString());

            Console.WriteLine(mail.Get());
            Console.ReadLine();
        }