regular expression valid email code example

Example 1: regular expression for email

^([a-zA-Z0-9_\-\.]+)@([a-zA-Z0-9_\-\.]+)\.([a-zA-Z]{2,5})$

Example 2: regular expression for email and mobile

$email=$_POST['email'];

$emailPattern = '/^\w{2,}@\w{2,}\.\w{2,4}$/'; 
$mobilePattern ="/^[7-9][0-9]{9}$/"; 

if(preg_match($emailPattern, $email)){
    echo "Email Success!";
} else if(preg_match($mobilePattern, $email)){
    echo "Mobile Success!";
} else {
    echo "Invalid entry";
}