(which is particularly important for mobile applications which may be contacting a server via slow Wifi or mobile networks)[email protected] Gallagher, you're right about performance.
However, from a security standpoint, client side JS wouldn't protect you from XSS, SQL injection, or other vulnerabilities.
To extend slightly, email addresses could also contain IP addresses, so this is potentially even more restrictive than described. We use validation to confirm that input matches our expectations in order to avoid trying to use badly formatted data in certain ways.
Regular expression is an art of the programing, it’s hard to debug , learn and understand, but the powerful features are still attract many developers to code regular expression.
: Finally, the email address must end with two to four alphabets.
Having a-z and A-Z means that both lowercase and uppercase letters are allowed.
indicates the minimum and maximum number of characters.
This will allow domain names with 2, 3 and 4 characters e.g.; us, tx, org, com, net, wxyz).
To validate email address on client side, we can use java script with regular expression.IMHO, it's best to do some basic validation on the front end so that your users don't lose the data they entered (EX: check for empty fields, validate phone numbers or SSN).Though this solution may be simple, I'm sure this is one of those useful things that people will be Googling for and deserves its own entry on the site If only Google would be the first place to look :) Just look at the duplicates of this closed every some time.This is a code snippet for basic Java Script to validate email address using a regular expression.This is building on my previous post on how to use regular expressions with j Query. Update 12/05/13: Separated into versions for testing.