In Javascript Regex, how to check that a string is a valid hex color?

Question

For a string like #fff443 or #999999

How to check that a string has:

• 7 characters, the first of which is a hash
• there are no characters in the string except the hash at the beginning

Answer 1

It seems that you are matching with css color:

 function isValidColor(str) { return str.match(/^#[a-f0-9]{6}$/i) !== null; } 

Develop:

^ start of the match
# hash [a-f0-9] any letter from af and 0-9
{6} previous group is displayed exactly 6 times
$ end of match
i ignore case