Something that I initially thought would be simple turned into hours of googling for solutions. The problem? I wanted to use JavaScript to check if a URL uses valid syntax.
What I ended up doing is use js-uri to parse the URLs I want to check and then use a couple of regular expressions to check the syntax of the URL parts it returns.
Where I’m using this I’m not particularly interested in checking that the domain exists or verifying that the URL is live – I just want to check that the path, query, and fragment parts do not use characters other than those described in RFC 3986.
Posted in JavaScript.