Sharing a date formatting function implemented in JavaScript_javascript skills

str = str.replace(/yyyy|YYYY/, this.getFullYear());
str = str.replace(/yy|YY/, (this.getYear() % 100) > 9 ? (this.getYear() % 100).toString() : '0' (this.getYear() % 100 ));
var month = this.getMonth() 1;
str = str.replace(/MM/, month > 9 ? month.toString() : '0' month);
str = str.replace(/M/g, month);

str = str.replace(/w|W/g, Week[this.getDay()]);

str = str.replace(/dd|DD/, this.getDate() > 9 ? this.getDate().toString() : '0' this.getDate());
str = str.replace(/d|D/g, this.getDate());

str = str.replace(/hh|HH/, this.getHours() > 9 ? this.getHours().toString() : '0' this.getHours());
str = str.replace(/h|H/g, this.getHours());
str = str.replace(/mm/, this.getMinutes() > 9 ? this.getMinutes().toString() : '0' this.getMinutes());
str = str.replace(/m/g, this.getMinutes());

str = str.replace(/ss|SS/, this.getSeconds() > 9 ? this.getSeconds().toString() : '0' this.getSeconds());
str = str.replace(/s|S/g, this.getSeconds());
Return str;
}