Send a Marketing Cloud Transactional Email w/ .NET

To send a transaction email using Marketing Cloud and .NET, you must do the following.

- Create the Email (in Email Studio)

- Use AMPScript for the replacement tags 

- Create a Triggered Send and Associate with Email Above  (http://help.marketingcloud.com/en/documentation/exacttarget/interactions/triggered_emails/triggered_emails_guide/how_to_create_a_triggered_email_message_interaction/)

- If you change the email template, pause the Triggered Send, Republish it, and start it again.

Thanks to Markus - https://salesforce.stackexchange.com/questions/178900/can-i-use-marketing-cloud-for-transactional-emails-just-like-mandrill#178906

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//uses the Nuget Package: ExactTarget.TriggerEmailSender

//.NET code

//create configuration
var config = new ExactTarget.TriggeredEmail.Core.Configuration.ExactTargetConfiguration
{
	ApiUserName = "myemail@example.com",
	ApiPassword = "myUbreakablePassWord!",
	//use your endpoint given to you by ET, login to MC and look at your url
	EndPoint = "https://webservice.s7.exacttarget.com/Service.asmx",
	//ClientId = 1111111,//optional business unit id
};


//name of the triggered send
var emailTemplateName = "trig--tran--test--password-reset";
			
//send email   
var recipientEmailAddress = "myemail@example.com";

var triggeredEmail = new ExactTarget.TriggeredEmail.Trigger.ExactTargetTriggeredEmail(
	emailTemplateName,
	recipientEmailAddress);

triggeredEmail.SubscriberKey = recipientEmailAddress; //not needed


//set replacement/merge tags
triggeredEmail.AddReplacementValue("first_name", "John");                        
triggeredEmail.AddReplacementValue("login_link", "http://www.example.com/login");

var emailTrigger = new ExactTarget.TriggeredEmail.Trigger.EmailTrigger(config);

//final call to actually send the email
emailTrigger.Trigger(triggeredEmail);


//MC Email and AMPScript
%%[
    Var @link
    Set @link = AttributeValue("login_link")

    Var @firstName
    Set @firstName = AttributeValue("first_name")

]%%
<p>Dear %%=v(@firstName)=%%</p>
<a href="%%=RedirectTo(@link)=%%">%%=v(@link)=%%</a>