Flutter Dart: RegEx to extract URLs from a String - regex

Question

This is my string:
window.urlVideo = 'https://node34.vidstreamcdn.com/hls/5d59908aea5aa101a054dec2a1cd3aff/5d59908aea5aa101a054dec2a1cd3aff.playlist.m3u8';
var playerInstance = jwplayer("myVideo");
var countplayer = 1;
var countcheck = 0;
playerInstance.setup({
sources: [{
"file": urlVideo
}],
tracks: [{
file: "https://cache.cdnfile.info/images/13f9ddcaf2d83d846056ec44b0f1366d/12.vtt",
kind: "thumbnails"
}],
image: "https://cache.cdnfile.info/images/13f9ddcaf2d83d846056ec44b0f1366d/12_cover.jpg",
});
function changeLink() {
window.location = "//vidstreaming.io/load.php?id=MTM0OTgz&title=Mairimashita%21+Iruma-kun+Episode+12";
}
window.shouldChangeLink = function () {
window.location = "//vidstreaming.io/load.php?id=MTM0OTgz&title=Mairimashita%21+Iruma-kun+Episode+12";
}
I am using flutter dart.
How can I get window.urlVideo URL link and image URL link and .vtt file link?
Or
How can I get a list of URLs from a String?
I tried finding a way with and without using RegEx but I couldn't.
Any help is apreciated

Answer 1

This may not be the complete regex, but this worked for me for randomly picked links:
void main() {
final text = """My website url: https://blasanka.github.io/
Google search using: www.google.com, social media is facebook.com, http://example.com/method?param=flutter
stackoverflow.com is my greatest website. DartPad share: https://github.com/dart-lang/dart-pad/wiki/Sharing-Guide see this example and edit it here https://dartpad.dev/3d547fa15849f9794b7dbb8627499b00""";
RegExp exp = new RegExp(r'(?:(?:https?|ftp):\/\/)?[\w/\-?=%.]+\.[\w/\-?=%.]+');
Iterable<RegExpMatch> matches = exp.allMatches(text);
matches.forEach((match) {
print(text.substring(match.start, match.end));
});
}
Result:
https://blasanka.github.io/
www.google.com
facebook.com
http://example.com/method?param=flutter
stackoverflow.com
https://github.com/dart-lang/dart-pad/wiki/Sharing-Guide
https://dartpad.dev/3d547fa15849f9794b7dbb8627499b00
Play with it here: https://dartpad.dev/3d547fa15849f9794b7dbb8627499b00

Answer 2

Try this,
final urlRegExp = new RegExp(
r"((https?:www\.)|(https?:\/\/)|(www\.))[-a-zA-Z0-9#:%._\+~#=]{1,256}\.[a-zA-Z0-9]{1,6}(\/[-a-zA-Z0-9()#:%_\+.~#?&\/=]*)?");
final urlMatches = urlRegExp.allMatches(text);
List<String> urls = urlMatches.map(
(urlMatch) => text.substring(urlMatch.start, urlMatch.end))
.toList();
urls.forEach((x) => print(x));

Answer 3

Getting just the https? and ftp url's that are in quotes is this :
r"([\"'])\s*((?:(?:https?|ftp):\/\/)(?:\S+(?::\S*)?#)?(?:(?:(?:[1-9]\d?|1\d\d|2[01]\d|22[0-3])(?:\.(?:1?\d{1,2}|2[0-4]\d|25[0-5])){2}(?:\.(?:[1-9]\d?|1\d\d|2[0-4]\d|25[0-4]))|(?:(?:[a-zA-Z0-9\u00a1-\uffff]+-?)*[a-zA-Z0-9\u00a1-\uffff]+)(?:\.(?:[a-zA-Z0-9\u00a1-\uffff]+-?)*[a-zA-Z0-9\u00a1-\uffff]+)*(?:\.(?:[a-zA-Z\u00a1-\uffff]{2,})))|localhost)(?::\d{2,5})?(?:\/(?:(?!\1|\s)[\S\s])*)?)\s*\1"
Where the Url is captured in group 2.
https://regex101.com/r/UPmLBl/1

Answer 4

Much safer to use a library like linkify instead of rolling your own regex.
/// Attempts to extract link from a string.
///
/// If no link is found, then return null.
String extractLink(String input) {
var elements = linkify(input,
options: LinkifyOptions(
humanize: false,
));
for (var e in elements) {
if (e is LinkableElement) {
return e.url;
}
}
return null;
}