If (like me when I first saw this) you AREN’T experienced at Regex, it takes a while to parse. The local string (the part of the email address that comes before the @) can contain any of these characters: is a valid email address. For this reason, for a time I began running any email address against the following regular expression instead: Simple, right? This is often the most I do and, when paired with a confirmation field for the email address on your registration form, can alleviate most problems with user error. They can get ridiculously convoluted as in the case above and, according to the specification, are often too strict anyway.
if a user have entered # or $ sign in his/her email address then this function will return false.
To fix this problem, you implement an activation system where, after registering, I am sent an email with a link I must click.
This is to verify that I actually own that email address before my account is activated.
The ending quotation mark must not be preceded by a backslash character (\).
If the character that follows @ is not an opening bracket, match one alphanumeric character with a value of A-Z, a-z, or 0-9, followed by zero or more occurrences of a word character or a hyphen, followed by zero or one alphanumeric character with a value of A-Z, a-z, or 0-9, followed by a period. To determine whether an email address is valid, pass the email address to the Mail Address. methods can be included in a library of regular expression utility methods, or they can be included as private static or instance methods in the application class.