I need to remove some text from a big string with start and end label. For example:
...
// THIS IS START
..
..
// THIS IS END
...
Above text is saved in an variable. And I need to remove all texts start with // THIS IS START to // THIS IS END. I know that I can remove them by split the string into lines and parse them line by line. But I am looking for a better solution. Whether I can use regex to achieve this? The difficult part for me is to use variables for start/end labels.
Use .replace to search for THIS IS START, lazy-repeat any character, up until THIS IS END:
const str = `...
// THIS IS START
..
foo
..
// THIS IS END
...
between
...
// THIS IS START
..
bar
..
// THIS IS END`;
console.log(str.replace(/(\/\/ THIS IS START)[\s\S]+?(\/\/ THIS IS END)/g, '$1\n$2'));If you don't want to include the // lines either, then don't bother capturing them, and replace with the empty string:
const str = `...
// THIS IS START
..
foo
..
// THIS IS END
...
between
...
// THIS IS START
..
bar
..
// THIS IS END`;
console.log(str.replace(/\s\/\/ THIS IS START[\s\S]+?\/\/ THIS IS END/g, ''));
This is a fairly simple case. You need to mask your / and make sure to match the "shortest possible" string with the [^]*? expression (.*? does not allow newlines!) between the start and end labels, but otherwise it is straightforward.
Edited, (after hint from @revo):
string.replace(/\/\/ THIS IS START[^]*?\/\/ THIS IS END/g,'')
The character class [^] allows all characters, including newlines etc.
I think it should be (with gs option)
var str = `
// THIS IS START
..
// THIS IS END`;
console.log(str.replace(/\/\/ THIS IS START\n(.+)\/\/ THIS IS END/gs, "$1"));
