我需要一个正则表达式来匹配字符串

Question

I have url like this

let url = " https://storage.cloud.google.com/dev-radius-backend/merchant/docs/1568875072010.jpg?organizationId=837717194226 "

I need to match the substring "/merchant/docs/1568875072010.jpg"

I have found regEx to find the base of the url, but since in this case the filname is in between and not the end, I could not write a regEx myself.

But I found a way, which is not very efficient

var pathArray = url.split('/');
var a = pathArray[6].split('?')
var fileName = '/' + pathArray[4] + '/' + pathArray[5] + '/' + a[0]

I would need fileName to be "/merchant/docs/1568875072010.jpg"

Answer 1

The following Regex matches the pattern:
\/[^\/]+\/[^\/]+\/[^\/]+(?=\.)\.[^?]+

Example:

 var url = 'https://storage.cloud.google.com/dev-radius-backend/merchant/docs/1568875072010.jpg?organizationId=837717194226'; var match = url.match(/\/[^\/]+\/[^\/]+\/[^\/]+(?=\.)\.[^?]+/); if (match) { console.log(match[0]); // "/merchant/docs/1568875072010.jpg" document.getElementById('result').innerText = match[0]; }

 <span id="result"></span>

An explanation of the Regex:
\/ - matches a literal /
[^\/]+ - matches anything other than a / at least once
(?=\.) - a positive lookahead asserting that what immediately follows the current position in the string is a literal dot
\. - matches a literal dot
[^?]+ matches anything that's not a literal question mark

Answer 2

Although your question is confusing to me. Confusion is between:

1: if you want to match /merchant/docs/1568875072010.jpg to be in url string then use includes method

var url = "https://storage.cloud.google.com/dev-radius-backend/merchant/docs/1568875072010.jpg?organizationId=837717194226";
if (str.includes("/merchant/docs/1568875072010.jpg")) {
   alert('file found in URL')
}

2: If you want to extract that information from url string:

console.log(new URL(url).pathname.replace("/dev-radius-backend", ""));