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Answer 1

+21 A:

You've got a couple of issues here.

Firstly, you're defining your code within an anonymous function. This construct:

(function() {
  ...
)();

does two things. It defines an anonymous function and calls it. There are scope reasons to do this but I'm not sure it's what you actually want.

You're passing in a code block to setTimeout(). The problem is that update() is not within scope when executed like that. It however if you pass in a function pointer instead so this works:

(function() {
  $(document).ready(function() {update();});

  function update() { 
    $("#board").append(".");
    setTimeout(update, 1000);     }
  }
)();

because the function pointer update is within scope of that block.

But like I said, there is no need for the anonymous function so you can rewrite it like this:

$(document).ready(function() {update();});

function update() { 
  $("#board").append(".");
  setTimeout(update, 1000);     }
}

or

$(document).ready(function() {update();});

function update() { 
  $("#board").append(".");
  setTimeout('update()', 1000);     }
}

and both of these work. The second works because the update() within the code block is within scope now.

I also prefer the $(function() { ... } shortened block form and rather than calling setTimeout() within update() you can just use setInterval() instead:

$(function() {
  setInterval(update, 1000);
});

function update() {
  $("#board").append(".");
}

Hope that clears that up.

cletus 2009-09-30 02:57:15

Thanks, It worked. Can anyone explain why it doesn't work the way it was? every example I've looked at is more similar to the formatting I've used.

Bolt_Head 2009-09-30 03:00:12

Oh, your still editing ha ha thanks.

Bolt_Head 2009-09-30 03:01:07

is w3schools really the best resource to reference this? he would have made the same mistake if he used that page as an example.

meder 2009-09-30 03:03:30

w3schools is correct in this case. The issue was a scope issue.

cletus 2009-09-30 03:25:23

w3schools is not correct in many cases and does not promote best practices in web standards. I suggest MDC: https://developer.mozilla.org/En/Window.setTimeout

meder 2009-09-30 03:28:19

Answer 2

+6 A:

setInterval(function() {
    $('#board').append('.');
}, 1000);

You can use clearInterval if you wanted to stop it at one point.

meder 2009-09-30 02:58:18

I haven't used setInverval before but it appears to be a more direct route of accomplishing my goal. Thanks

Bolt_Head 2009-09-30 03:10:35

cletus seemed to have added it to his solution; the important thing to learn is that you should feed a real function to setInterval/setTimeout, not a string that will be evaluated eg 'update()'

meder 2009-09-30 03:14:01

Passing a code block like 'update()' is valid but not preferred.

cletus 2009-09-30 03:26:00

Answer 3

+2 A:

SetTimeout is used to make your set of code to execute after a specified time period so for your requirements its better to use setInterval because that will call your function every time ata specified time interval.

Goysar 2009-12-22 04:42:59

Answer 4

A:

$(document).ready(function(){ alert("HI");});

aasdfsdfsdfs 2010-10-25 12:38:51

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JQuery, setTimeout not working.

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