How to validate an email in php5?

I have use ereg to validate email address. But it gives an error.
return ereg("^[a-zA-Z0-9]+[a-zA-Z0-9_-]+@[a-zA-Z0-9]+[a-zA-Z0-9.-]+[a-zA-Z0-9]+.[a-z]{2,4}$", $email);
Deprecated: Function ereg() is deprecated



PHP5 does not support ereg function.so the alternative way is to use the filter_var() function, which gives you a lot of handy validation and sanitization options.

filter_var($email, FILTER_VALIDATE_EMAIL)

If you don't want to change your code that relied on your function, just do:

function isValidEmail($email){ 
    return filter_var($email, FILTER_VALIDATE_EMAIL);
}

MORE http://php.net/manual/en/function.filter-var.php