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Can we modify built-in object prototypes in JavaScript
Following is the code for modifying built-in object prototypes in JavaScript −
Example
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8" /> <meta name="viewport" content="width=device-width, initial-scale=1.0" /> <title>Document</title> <style> body { font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif; } .result { font-size: 20px; font-weight: 500; color: blueviolet; } </style> </head> <body> <h1>Modify built-in object prototypes</h1> <div class="result"></div> <br /> <button class="Btn">Click Here</button> <h3>Click on the above button to call the alert method</h3> <script> let resEle = document.querySelector(".result"); let BtnEle = document.querySelector(".Btn"); window.alert = function (msg) { resEle.innerHTML = "Custom Alert function has been triggered<br>"; resEle.innerHTML += "Alert Message = " + msg; }; BtnEle.addEventListener("click", () => { alert("Hello World"); }); </script> </body> </html> Output
On clicking the ‘Click Here’ button −
Updated on: 2020-07-18T07:56:14+05:30
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