I created a function that should check if a string correspond to an url format:
const test = (str) => {
const t = new RegExp(
'^(https?:\\/\\/)?' +
'(www\\.)' +
'((([a-z\\d]([a-z\\d-]*[a-z\\d])*)\\.)+[a-z]{2,}|)' +
'(\\#[-a-z\\d_]*)?$',
'i',
);
return t.test(str);
};
console.log(test('http://demo.com')); //expect true
console.log(test('http://ww.demo.com')); //expect falseFor each console.log() i wrote the expected value, in both cases i got false. In the last case false is ok, but in the first i should get true. How to fix the regex?
Even if this answer is a bit too much for this Problem, it illustrates the problem: Even if it might be possible to create a regexp to check the url, it is much simpler and more robust to parse the URL and "create a real Object", on/with which the overall test can be decomposed to a number of smaller tests.
So probably the builtin URL constructor of modern browsers may help you here (link1, link 2).
One approach to test you url might look like this:
function testURL (urlstring) {
var errors = [];
try {
var url = new URL(urlstring);
if (!/https/.test(url.protocol)) {
errors.push('wrong protocol');
}
//more tests here
} catch(err) {
//something went really wrong
//log the error here
} finally {
return errors;
}
}if (testURL('mr.bean').length == 0) { runSomething(); }