<html><body><p id="demo">Click the button to create an array, call the new ucase() method, and display the result.</p><button onclick="myFunction()">Try it</button><script>Array.prototype.myUcase=function(){for (i=0;i<this.length;i++) { this[i]=this[i].toUpperCase(); }}function myFunction(){var fruits = ["Banana", "Orange", "Apple", "Mango"];fruits.myUcase();var x=document.getElementById("demo");x.innerHTML=fruits;}</script></body></html>