Javascript regular expression: remove first and last slash

Question

I have these strings in javascript:

/banking/bonifici/italia
/banking/bonifici/italia/

and I would like to remove the first and last slash if it's exists.

I tried ^\/(.+)\/?$ but it doesn't work.

Reading some post in stackoverflow I found that php has trim function and I could use his javascript translation ( http://phpjs.org/functions/trim :566) but I would prefer a "simple" regular expression.

Answer 1

return theString.replace(/^\/|\/$/g, '');

“用空字符串替换所有（ /.../g ）前斜杠（ ^\\/ ）或（ | ）后斜杠（ \\/$ ）。”

Answer 2

There's no real reason to use a regex here, string functions will work fine:

var string = "/banking/bonifici/italia/";
if (string.charAt(0) == "/") string = string.substr(1);
if (string.charAt(string.length - 1) == "/") string = string.substr(0, string.length - 1);
// string => "banking/bonifici/italia"

See this in action on jsFiddle .

References:

• String.substr
• String.charAt

Answer 3

In case if using RegExp is not an option , or you have to handle corner cases while working with URLs (such as double/triple slashes or empty lines without complex replacements), or utilizing additional processing, here's a less obvious, but more functional-style solution:

 const urls = [ '//some/link///to/the/resource/', '/root', '/something/else', ]; const trimmedUrls = urls.map(url => url.split('/').filter(x => x).join('/')); console.log(trimmedUrls); 

In this snippet filter() function can implement more complex logic than just filtering empty strings (which is default behavior).

Word of warning - this is not as fast as other snippets here.

Answer 4

One liner, no regex, handles multiple occurences

const trimSlashes = str => str.split('/').filter(v => v !== '').join('/');

console.log(trimSlashes('/some/path/foo/bar///')); // "some/path/foo/bar"

Answer 5

Just in case that someone needs a premature optimization here...

http://jsperf.com/remove-leading-and-trailing-slashes/5

var path = '///foo/is/not/equal/to/bar///'
var count = path.length - 1
var index = 0

while (path.charCodeAt(index) === 47 && ++index);
while (path.charCodeAt(count) === 47 && --count);

path = path.slice(index, count + 1)

Answer 6

you can check with str.startsWith and str.endsWith then substr if exist

  var str= "/aaa/bbb/";
  var str= str.startsWith('/') ? str.substr(1) : str;
  var str= str.endsWith('/') ? str.substr(0,str.length - 1) : str;

or you can write custom function

trimSlashes('/aaa/bbb/');

function trimSlashes(str){
  str= str.startsWith('/') ? str.substr(1) : str;
  str= str.endsWith('/') ? str.substr(0,str.length - 1) : str;
  return str;
}