Nodejs Utililty Methods String Case Convert

String.prototype.toAkaLowerCase = function() {
    var integer=0,i;
    var newString="";
    for(i=0;i<this.length;i++){
      var integer = this.charCodeAt(i);
      if(integer>=65 && integer<=90){
        integer=integer+32;
        newString=newString+String.fromCharCode(integer);
      else{
        newString=newString+String.fromCharCode(integer);
    return newString;
  };

String.prototype.toAkaUpperCase = function() {
  var integer=0,i;
  var newString="";
  for(i=0;i<this.length;i++){
    var integer = this.charCodeAt(i);
    if(integer>=97 && integer<=122){
      integer=integer-32;
      newString=newString+String.fromCharCode(integer);
    else{
      newString=newString+String.fromCharCode(integer);
  return newString;
};

String.prototype.toAlternatingCase = function() {
  return [...this].map(
    (c) => (c === c.toUpperCase() ? c.toLowerCase() : c.toUpperCase()),
  ).join``;
};

String.prototype.toAlternatingCase = function () {
  var _str = ""; 
  for(var _c = 0; _c < this.length; _c++){
    _str += ((this[_c] === this[_c].toUpperCase())? this[_c].toLowerCase() : this[_c].toUpperCase());
  return _str;

String.prototype.toAlternatingCase = function () {
  var result = [];
  var letters = this.split("");
  letters.forEach(function(char) {
    if ((char.charCodeAt(0) >= 97) && (char.charCodeAt(0) <= 122)) {
      result.push(char.toUpperCase());
    } else if ((char.charCodeAt(0) >= 65) && (char.charCodeAt(0) <= 90)){
      result.push(char.toLowerCase());
    } else {
...

String.prototype.toAlternatingCase = function () {
  var newStr = "";
  for (var i = 0; i < this.length; i++){
    if (this.charAt(i).toUpperCase() === this.charAt(i)){
       newStr += this.charAt(i).toLowerCase();
    } else {
       newStr += this.charAt(i).toUpperCase();  
  return newStr;

String.prototype.toAlternatingCase = function () {
  return this.toString().split('')
                        .map(l => l.match(/[a-z]/)  ? l.toUpperCase() : l.toLowerCase())
                        .join('');

String.prototype.toAlternatingCase = function() {
  var output = '';
  for (var i=0; i<this.length; i++) {
    if (this[i].toLowerCase() === this[i]) {
      output = output + this[i].toUpperCase();
    } else if (this[i].toUpperCase() === this[i]) {
      output = output + this[i].toLowerCase();
    } else {
      output = output + this[i];
...

String.prototype.snakeCase = function() {
  return this.replace( /([A-Z])/g, function( $1 ) {return "_" + $1.toLowerCase();} );
};

String.prototype.snakeCaseDash = function() {
  return this.replace( /([A-Z])/g, function( $1 ) {return "-" + $1.toLowerCase();} );
};