http://stackoverflow.com/questions/7798748/find-out-whether-chrome-console-is-open
In my case,
I use check4.js
check1.js, check2.js code can't check developer tools open event.
check3.js code check using setInterval() function.
check4.js
code use Object definedProperty() function on get() function.
console.log("%c hello", element)
When console.log called, element object call get() function.
And you can check developer tools open
Happy Coding!
