How to make allowed values are 1 to 7, n and blank only?

Hello,

You can do it with a regular expression which tests for any of the permitted characters. E.g.

Code:

/^[1-7n]?$/

This will match a string of one character in length, consisting of the digits one to seven or an 'n'
The question mark makes everything optional, which means that if the field is submitted empty, validation will still pass.

Code:

<!DOCTYPE html> <html> <head> <meta charset="utf-8" /> <title>Validate score</title> </head> <body> <form id="myForm"> <p> <label for="firstName">Please enter your score:</label> <input type="text" id="score" /> </p> <input type="submit" value="Submit"> </form> <script> var f = document.getElementById('myForm'); f.onsubmit = function(){ if(!(/^[1-7n]?$/).test(f.score.value)){ alert(f.score.value + "is an invalid value! Allowed values are 1 to 7, n and blank"); return false } } </script> </body> </html>