JavaScript RegExp to recognize specific file extension

Question

Is there a way how to write a JavaScript regular expression that would recognize .ts file extension for this:

"file.ts"

but would fail on this:

"file.vue.ts"

What I need is, if the file name ends with .vue.ts, it shouldn't be handled as a .ts file.

I've tried a lot of things with no success.

Update: It needs to be a regular expression, because that's what I'm passing to a parameter of a function.

/(.*).ts$/ this should check that the last 3 chars are '.ts' — PRDeving, Mar 22 '18 at 17:49
Possible duplicate of [Regex JavaScript image file extension](https://stackoverflow.com/questions/10473185/regex-javascript-image-file-extension) — Scott Weaver, Mar 22 '18 at 17:50
Possible duplicate of [Javascript regex for matching/extracting file extension](https://stackoverflow.com/questions/6582171/javascript-regex-for-matching-extracting-file-extension) — Aman B, Mar 22 '18 at 17:50
how do you know, that `.vue.ts` is another file extension and not another name with a dot? — Nina Scholz, Mar 22 '18 at 17:52
@sweaver2112 I have tried searching for the solution for several hours, that's why I'm here. If you could provide the answer or a link from Google, I would be grateful. — Tom Shane, Mar 22 '18 at 17:59

Nina Scholz · Answer 1 · 2018-03-22T17:55:52.357

3

You could look for a previous coming dot and if not return true.

console.log(["file.ts", "file.vue.ts"].map(s => /^[^.]+\.ts$/.test(s)));

edited Mar 22 '18 at 17:55

answered Mar 22 '18 at 17:49

Nina Scholz

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yajiv · Accepted Answer · 2018-03-22T18:12:06.163

3

Regex for that is ^[^.]+.ts$

var x=/^[^.]+.ts$/;
console.log(x.test("file.ts"));
console.log(x.test("file.vue.ts"));
console.log(x.test("file.vue.ts1"));

Explanation:-

^[^.]+.ts$

^        ---> start of line
[^.]+    ---> match anything which is not '.' (match atleast one character)
^[^.]+   ---> match character until first '.' encounter
.ts      ---> match '.ts'
$        ---> end of line
.ts$     ---> string end with '.ts'

edited Mar 22 '18 at 18:12

answered Mar 22 '18 at 17:53

yajiv

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I need it not to match for "file.vue.ts". Your expression results in a match in this case. – Tom Shane Mar 22 '18 at 17:57

score 1 · Answer 3 · answered Mar 22 '18 at 18:00

1

This will work except for special characters. Will allow for uppercase letters, lowercase letters, numbers, underscores, and dashes:

^[a-zA-Z0-9\_\-]+(\.ts)$

answered Mar 22 '18 at 18:00

John Paul Smithdeal

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score 1 · Answer 4 · answered Mar 22 '18 at 18:01

1

const regex = /(.*[^.vue]).ts/g;
abc.ts.ts Matches
abc.xyx.htm.ts Matches
abc.vue.ts Fails
xyz.abx.sxc.vue.ts Fails

Javascript regex should be this one.

answered Mar 22 '18 at 18:01

Nadeem Ahmad

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"file.ts" won't pass, because of "e" in "file", I guess. – Tom Shane Mar 22 '18 at 20:31

JavaScript RegExp to recognize specific file extension

4 Answers4