Javascript：仅删除尾随空格

Question

Can anyone help me on how to remove trailing spaces in JavaScript. I want to keep the leading spaces as is and only remove trailing spaces.
EG: ' test ' becomes ' test' . Seems like pretty simple but I can't figure it out.

PS: I am pretty sure I can't be the first one to ask this but I can't find an answer in SO. Also, I am looking for JavaScript solution. I am not using jQuery.

Answer 1

Use String#replace with regex /\s+$/ and replacing text as empty string.

string.replace(/\s+$/, '')

 console.log( '-----' + ' test '.replace(/\s+$/, '') + '-----' )

Answer 2

"    test    ".replace(/\s+$/g, '');

Answer 3

use trimRight()

var x ="   test   "

x.trimRight()

Answer 4

有一种方法可以在替换方法中创建正则表达式，例如 str.replace(/\s+$/g,'') 将删除所有尾随空格。

Answer 5

Regex is worth knowing. But in case you don't, and don't want to use code you're not comfortable with, nor dive down that rabbit-hole for your current issue, here's a simple manual workaround:

let endTrim = ((str) => {
  let i = str.length - 1
  while(str[i] === ' ') {
    str = str.slice(0,i)
    i--
  }
  return str
})

Answer 6

Update 2019

String trim methods have been added to ECMAScript spec in 2019 with wide browser support

• String.trim()
• String.trimStart()
• String.trimEnd()

You can use like this:

" test ".trimEnd() // " test"

Further Reading

• tc39 proposal - String.prototype.{trimStart,trimEnd}