Here you can find the source of upcase()
String.prototype.upcase = function(){ return this.toUpperCase(); };
String.prototype.ucwords = function(){ var arr = this.split(' '); var str =''; arr.forEach(function(v){ str += v.charAt(0).toUpperCase()+v.slice(1,v.length)+' '; }); return str; };
String.prototype.ucwords = function(){ return this.replace(/(?:^|\s)\S/g,function(v){return v.toUpperCase();}); };
String.prototype.ucwords = function () { return this.toLowerCase().replace(/^.|\s\S/g, function (a) { return a.toUpperCase(); }); };
String.prototype.upWord = function (){ var words = this.split(" "); var newWords = words.map(function(elem,index) { return (elem[0].toUpperCase() + elem.slice(1)); }) return newWords.join(" "); var str = "the quick fox jump over the lazy dog"; console.log(str.upWord()); ...
String.prototype.upcase = function () { return this.valueOf().toUpperCase(); };
String.prototype.upperCaseFirst = function() { return this.replace(/^./, function(a) { return a.toUpperCase(); }); };
String.prototype.upperFirstChar = function() { return this.charAt(0).toUpperCase() + this.slice(1)
String.prototype.upperFirstLetter = function() { return this.charAt(0).toUpperCase() + this.slice(1);
String.prototype.upperInitial = function() { return this.replace(/(^|\s+)\w/g, function(s) { return s.toUpperCase(); }); };