Use an Array as the warning message:
var myArr = ["Orange", "Banana", "CSS", "HTML" ]; console.warn(myObj);
Press F12 on your keyboard to view the message in the console view.
<!DOCTYPE html> <html> <body> <script> var myArr = ["Orange", "Banana", "CSS", "HTML" ]; console.warn(myArr); </script>//from w ww.jav a 2 s . c o m </body> </html>