I must be missing something quite obvious here because something rather strange is happening

I have a bit of js code that goes pretty much like this

setTimeout(myFn(), 20000);

If I m correct when I hit that line, after 20 seconds myFn should run right?

in my case myFn is an ajax call and it happens quite fast ( not at 20seconds and I just dont understand why. Any ideas or pointers?

I must be missing something quite obvious here because something rather strange is happening

I have a bit of js code that goes pretty much like this

setTimeout(myFn(), 20000);

If I m correct when I hit that line, after 20 seconds myFn should run right?

in my case myFn is an ajax call and it happens quite fast ( not at 20seconds and I just dont understand why. Any ideas or pointers?

• javascript
• dom-events

• Someone had the same mistake last night. Is this the new popular JavScript mistake to make? – Nosredna Commented Nov 24, 2009 at 16:22
• When I first moved out of the service side code into the client side it was my first mistake... – JoshBerke Commented Nov 24, 2009 at 16:26

4 Answers 4

Try

setTimeout(myFn,20000);

When you say setTimeout(myFn(),20000) your telling it to evaluate myFn() and call the return value after 20 seconds.

The problem is that myFn() is a function call not function pointer. You need to do:

 setTimeout(myFn, 20000);

Otherwise the myFn will be run before the timer is set.

No, the correct line would be setTimeout(myFn, 20000);

In yours, you're actually calling the myFn without delay, on the same line, and its result is scheduled to run after 20 seconds.

Remove the (). If you put them, the function is called directly. Without them, it passed the function as argument.