[javascript] Return string without trailing slash

I have two variables:

site1 = "www.somesite.com";  
site2 = "www.somesite.com/";  

I want to do something like this

function someFunction(site)
{
    // If the var has a trailing slash (like site2), 
    // remove it and return the site without the trailing slash
    return no_trailing_slash_url;
}

How do I do this?

function stripTrailingSlash(text) {
    return text
        .split('/')
        .filter(Boolean)
        .join('/');
}

another solution.

Some of these examples are more complicated than you might need. To remove a single slash, from anywhere (leading or trailing), you could get away with something as simple as this:

let no_trailing_slash_url = site.replace('/', '');

Complete example:

let site1 = "www.somesite.com";  
let site2 = "www.somesite.com/";  

function someFunction(site)
{
    let no_trailing_slash_url = site.replace('/', '');
    return no_trailing_slash_url;
}

console.log(someFunction(site2)); // www.somesite.com

Note that .replace(...) returns a string, it does not modify the string it is called on.

function stripTrailingSlash(str) {
    if(str.substr(-1) === '/') {
        return str.substr(0, str.length - 1);
    }
    return str;
}

Note: IE8 and older do not support negative substr offsets. Use str.length - 1 instead if you need to support those ancient browsers.

This snippet is more accurate:

str.replace(/^(.+?)\/*?$/, "$1");

1. It not strips / strings, as it's a valid url.
2. It strips strings with multiple trailing slashes.

ES6 / ES2015 provides an API for asking whether a string ends with something, which enables writing a cleaner and more readable function.

const stripTrailingSlash = (str) => {
    return str.endsWith('/') ?
        str.slice(0, -1) :
        str;
};

The easies way i know of is this

function stipTrailingSlash(str){
   if(srt.charAt(str.length-1) == "/"){ str = str.substr(0, str.length - 1);}
   return str
}

This will then check for a / on the end and if its there remove it if its not will return your string as it was

Just one thing that i cant comment on yet @ThiefMaster wow you dont care about memory do you lol runnign a substr just for an if?

Fixed the calucation for zero-based index on the string.

I know the question is about trailing slashes but I found this post during my search for trimming slashes (both at the tail and head of a string literal), as people would need this solution I am posting one here :

'///I am free///'.replace(/^\/+|\/+$/g, ''); // returns 'I am free'

UPDATE:

as @Stephen R mentioned in the comments, if you want to remove both slashes and backslashes both at the tail and the head of a string literal, you would write :

'\/\\/\/I am free\\///\\\\'.replace(/^[\\/]+|[\\/]+$/g, '') // returns 'I am free'

Based on @vdegenne 's answer... how to strip:

Single trailing slash:

theString.replace(/\/$/, '');

Single or consecutive trailing slashes:

theString.replace(/\/+$/g, '');

Single leading slash:

theString.replace(/^\//, '');

Single or consecutive leading slashes:

theString.replace(/^\/+/g, '');

Single leading and trailing slashes:

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

Single or consecutive leading and trailing slashes:

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

To handle both slashes and backslashes, replace instances of \/ with [\\/]

function someFunction(site) {
  if (site.indexOf('/') > 0)
    return site.substring(0, site.indexOf('/'));
  return site;
}

Here a small url example.

var currentUrl = location.href;

if(currentUrl.substr(-1) == '/') {
    currentUrl = currentUrl.substr(0, currentUrl.length - 1);
}

log the new url

console.log(currentUrl);

I'd use a regular expression:

function someFunction(site)
{
// if site has an end slash (like: www.example.com/),
// then remove it and return the site without the end slash
return site.replace(/\/$/, '') // Match a forward slash / at the end of the string ($)
}

You'll want to make sure that the variable site is a string, though.