多个sendgrid电子邮件到短信电子邮件地址都不正常

Question

When my .NET (2015) windows app, on my Azure Windows server 2012 VM, needs to send a message that is over 160 characters to an email address to SMS text message service on a mobile, my app cuts the long message into 'chunks' each less than 160 chars, and then uses SendGrid to email each chunk.

But they don't arrive in the order sent. How do I fix this?

I've tried inserting a delay (thread.sleep) between each chunk, but that doesn't work.

Answer 1

You can't really. You have no control over when and the order that the text messages will be delivered/received by the end users phone. What you could try to do is break the message up and in your loop wait a minute before sending the next chunk. There's no guarantee this will work though and it sounds like you already tried this.

Compounding the issue is using SendGrid or any ESP (Email Service Provider). When you send a request to most ESP's they queue up requests and send them. So even if you wait a minute to send your requests, they might get lined up in the queue and sent by the ESP all with in seconds of each other.

You might want to try using an SMS/MMS service provider like Twilio to send text messages. Some of these services have logic already to break up messages that are too long into chunks automatically for you and have probably already worked on solving, as best they can, the out of order issue.