JSFiddle - React, Tailwind, and code Playground

JavaScript

function cleanUp(url) {
url = url.replace(new RegExp(/^\s+/),""); // START
url = url.replace(new RegExp(/\s+$/),""); // END
 
// IF FOUND, CONVERT BACK SLASHES TO FORWARD SLASHES
url = url.replace(new RegExp(/\\/g),"/");
 
// IF THERE, REMOVES 'http://', 'https://' or 'ftp://' FROM THE START
url = url.replace(new RegExp(/^http\:\/\/|^https\:\/\/|^ftp\:\/\//i),"");
 
// IF THERE, REMOVES 'www.' FROM THE START OF THE STRING
url = url.replace(new RegExp(/^www\./i),"");
    //remove slash from end
url = url.replace(new RegExp(/\/$/i),"");    
return url;
}

alert(cleanUp('http://google.com'));