Javascript setInterval clearInterval Simple Example Not Working Explained?

Question

I have a very simple JS setInterval and clearInterval example that doesn\'t work. There has got to be an underlying reason why it does not work and I would like to know why

Answer 1

automessage is declared twice - as a global variable and as a local variable. try:

function turnON() //executed by onclick event A
{
    automessage = setInterval(function(){ something() }, 2000);
}