JavaScript - Validating a Hex in Opera?

Question

Hi,

This function works in Firefox, Chrome, IE9. Doesn't work in Opera.

function isValidHex(hex) { alert(hex);
    var strPattern = /^#([0-9a-f]{1,2}){3}$/i; alert(strPattern.test(hex));
    return strPattern.test(hex);
}

The hex going in is the same. The result of strPatter.test returns false in Opera and true in Firefox.

Tested.

#000000
#ffffff

Any ideas?

Answer 1

This regex is incorrect. #1234 would be correct too in this regex. User the regex /^#([a-zA-Z0-9]{3}|[a-zA-Z0-9]{6})$/.

Answer 2

If you swap the multipliers around, it works in Opera also:

function isValidHex(hex) {
  var objPattern = /^#([0-9a-f]{3}){1,2}$/i;
  return objPattern.test(hex);
}

You would want to do that anyway, so that you match one or two groups of three digits (i.e. 3 or 3+3 characters), not three groups of one or two digits (i.e. 1+1+1, 2+1+1, 2+2+1 or 2+2+2 characters).

(Note that I also renamed the varaible from strPattern to objPattern as it contains a regular expression object, not a string. If you are using hungarian notation to specify the data type, the prefix has to match the actual data type, or it's only contraproductive.)