Use of sendEmail in loops
Why is this an issue?
Salesforce limits the number of Messaging.sendEmail() calls to 10 per transaction. Placing email sends inside a loop will quickly exceed this limit, causing the transaction to fail.
Examples
Example of incorrect code:
for (Contact c : contacts) {
Messaging.SingleEmailMessage mail = new Messaging.SingleEmailMessage();
mail.setToAddresses(new String[]{c.Email});
mail.setSubject('Welcome');
Messaging.sendEmail(new List<Messaging.SingleEmailMessage>{mail});
}
Example of correct code:
List<Messaging.SingleEmailMessage> emails = new List<Messaging.SingleEmailMessage>();
for (Contact c : contacts) {
Messaging.SingleEmailMessage mail = new Messaging.SingleEmailMessage();
mail.setToAddresses(new String[]{c.Email});
mail.setSubject('Welcome');
emails.add(mail);
}
Messaging.sendEmail(emails); // Single call, up to 5000 emails
How can I fix violations?
Collect emails in a list: Build a list of
SingleEmailMessageobjects inside the loop.Send all at once: Call
Messaging.sendEmail()once after the loop with the full list.
Note: A single sendEmail() call can send up to 5,000 emails.
Resources