JavaScript regexp - new lines and empty spaces at start and end of a string

Question

const dummyText = `First line
                              Second line
                                                       Third line


    Last Line`

const expectedOutput = `First Line
Second line
Third line
Last Line`

dummyText.replace(/ +?/g, ''), this regex currently replacing all the spaces in between words. I need to remove spaces start and end of the string, have to preserve newline

Below output currently I'm getting

FirstLine Secondline Thirdline LastLine

I need output like expectedOutput variable value

`/^ +| +$/gm` - `m` the Multiline modifier so that `^` and `$` are start- and end-of-line respectively instead of -of-string. — Niet the Dark Absol, Jul 13 '20 at 17:37
`dummyText.split("\n").map(x => x.trim()).filter(Boolean).join("\n")` — Wiktor Stribiżew, Jul 13 '20 at 17:40
@NiettheDarkAbsol, Fantastic, your solution working great. Thanks for your help. — Arun M, Jul 13 '20 at 17:50
@WiktorStribiżew, Your solution also working well. thanks for your help. — Arun M, Jul 13 '20 at 17:50

score 0 · Answer 1 · answered Jul 13 '20 at 17:41

Without a fancy regular expression it can be a split, trim, filter, and join

const dummyText = `First line
                          Second line
                                                   Third line


Last Line`

const result = dummyText
  .split(/\n/)   // split on new lines
  .map(x => x.trim()) //clean up the new lines
  .filter(Boolean)  // remove empty lines
  .join('\n')  // join it back together
console.log(result);

score -2 · Answer 2 · answered Jul 13 '20 at 17:39

-2

It's possible to use .trim() to remove all spaces

const greeting = '   Hello world!   ';

console.log(greeting);
// expected output: "   Hello world!   ";

console.log(greeting.trim());
// expected output: "Hello world!";

answered Jul 13 '20 at 17:39

Lucas Hubert

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JavaScript regexp - new lines and empty spaces at start and end of a string

2 Answers2