IsValid

Parameters:

String username

String password

String email

EmailValidationLevel level

Option[] options

EmailValidationResult

Checks an email address for validity at the requested level.

The following level values are currently supported:

Syntax. The supplied email is checked to ensure that it meets the standard email address format.
This is the quickest option and would reject such incorrect email addresses as "noone@nowhere" and "N/A", but would accept incorrect email addresses that are correctly formed but that do not include a valid domain name such as "noone@data-9.com"
MX. The supplied email is checked to ensure that the domain name (the part to the right of the @ sign) exists and is set up to receive email.
This is still normally very quick, but can take a few seconds in some cases. This check would reject incorrectly formatted email addresses in the same way as the Syntax check, and would also reject a misspelled domain name such as "noone@data-9.com". It can also detect when a domain name exists but does not handle email, such as "noone@example.com".

It does not verify that the part of the email address to the left of the @ sign exists.

The return value can be one of the following options:

Valid. According to the selected level of validation, the email address appears to be valid. This is not an absolute guarantee that emails sent to this address will be delivered and read.
Invalid. The email address is invalid. This is a definite assessment that emails sent to this address cannot be delivered.
Inconclusive. A precise Valid or Invalid result could not be determined. This is normally because the server being used for the address being checked did not respond in time, or did not provide sufficient information.