使用JavaScript正则表达式删除'&&&'之后的字符串的最后一部分

Question

I'm trying to use a regex in JS to remove the last part of a string. This substring starts with &&& , is followed by something not &&& , and ends with .pdf .

So, for example, the final regex should take a string like:

parent&&&child&&&grandchild.pdf

and match

parent&&&child

I'm not that great with regex's, so my best effort has been something like:

.*?(?:&&&.*\.pdf)

Which matches the whole string. Can anyone help me out?

Answer 1

You may use this greedy regex either in replace or in match :

 var s = 'parent&&&child&&&grandchild.pdf'; // using replace var r = s.replace(/(.*)&&&.*\\.pdf$/, '$1'); console.log(r); //=> parent&&&child // using match var m = s.match(/(.*)&&&.*\\.pdf$/) if (m) { console.log(m[1]); //=> parent&&&child } 

By using greedy pattern .* before &&& we make sure to match **last instance of &&& in input.

Answer 2

You want to remove the last portion, so replace it

 var str = "parent&&&child&&&grandchild.pdf" var result = str.replace(/&&&[^&]+\\.pdf$/, '') console.log(result)