javascript - How to customize regular expression which let user can input number from zero to nine? -

i have below regular expression email validation want customize regular user can input number 0 nine.

example: heng18374sopheak@yahoo.com, 12948sopheak@yahoo.com, sopheak876@gmail.com

here email validation let user input character can't input number

this email validation regular expression avoid user input number (0-9) want user can input number(0-9).so how customize below regular expression?

/(^[a-z]([a-z_\.]*)@([a-z_\.]*)([.][a-z]{3})$)|(^[a-z]([a-z_\.]*)@([a-z_\.]*)(\.[a-z]{3})(\.[a-z]{2})*$)/i 

but want customize code let user input number 0 nine.

thanks help

/(^[a-z-0-9]([a-z_\.0-9]*)@([a-z_\.]*)([.][a-z]{3})$)|(^[a-z]([a-z_\.]*)@([a-z_\.]*)(\.[a-z]{3})(\.[a-z]{2})*$)/i 

simply add 0-9 pattern.