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You would need to put the alerts inside the post callback as well. The request response is probably coming back AFTER all of the JS has been processed on page load.
Blair
<div><span class="gmail_quote">On 12/5/06,
<b class="gmail_sendername">kazaar</b> <<a href="mailto:smarko@gmail.com">smarko@gmail.com</a>> wrote:</span><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
How should I change the following, so those 2 global variables would be
filled with information returned by server? Code below doesn't do it. Could
this have something to do with asyncronous loading or something?
var seed_id;
var seed;
function createSeed() {
    $.post('login/login.php',{action:'createseed'}, function(data) {
      results = data.split('|');
      seed_id = results[0];
      seed = results[1];
      alert(seed_id+"|"+seed); // something like.. 1325|2ae5fa6e56fae5f67a5e
    });
    alert(seed_id+"|"+seed); // undefined|undefined
}
createSeed();
alert(seed_id+"|"+seed); // undefined|undefined
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Like Blair says, you need to use a callback.
I'd do something like this:
var seed_id;
var seed;
function createSeed(callback) {
   $.post('login/login.php',<div style="direction: ltr;">{action:'createseed'}, function(data) {
     results = data.split('|');
     seed_id = results[0];
     seed = results[1];
     if (callback) callback.call();
   });
}
createSeed(function() {
  alert(seed_id+"|"+seed);
});
</div>
That should give you the proper values in the alert.
Chris
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Thank you for quick answers. However, problem still exists. Latter
alert-function would still fail, because variables wouldn't be set yet at
that moment (I will need those variables later in another call to server).
Problem falls back to asyncronous loading. Isn't there an easy way to use
syncronous loading, without touching jquery.js -file itself?
var seed_id;
var seed;
[...]
createSeed(function() {
alert(seed_id+"|"+seed);
});
alert(seed_id+"|"+seed);
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Synchronous loading is proposed for jQuery 1.1. But I'm sure callbacks would be able to do what you need...
Couldn't you just do:
createSeed(restOfScript);
function restOfScript() {
...
}
Then the rest of the script would run after the ajax request has returned.
Chris
<div><span class="gmail_quote">On 06/12/06, <b class="gmail_sendername">kazaar</b> <<a href="mailto:smarko@gmail.com">smarko@gmail.com
</a>> wrote:</span><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
Thank you for quick answers. However, problem still exists. Latter
alert-function would still fail, because variables wouldn't be set yet at
that moment (I will need those variables later in another call to server).
Problem falls back to asyncronous loading. Isn't there an easy way to use
syncronous loading, without touching jquery.js -file itself?
var seed_id;
var seed;
[...]
createSeed(function() {
  alert(seed_id+"|"+seed);
});
alert(seed_id+"|"+seed);
--
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<a href="http://Nabble.com">Nabble.com</a>.
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Ok, I'm choosing that path while waiting for jQuery 1.1. Works fine. It's not
so critical issue, but the resulting code looks.. well, silly.
Chris Domigan

Having your scripts broken down into several functions isn't at all an ugly way to do things. IMHO everything should be in a function except for globals. Makes program control a lot easier :)
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Chris Domigan schrieb:

I'm aware of this, but there can be situations where script can not be
allowed to continue, before certain "stuff" has been done for sure.
Klaus Hartl-3

Chris Domigan

On 07/12/06, <b class="gmail_sendername">kazaar</b> <<a href="mailto:smarko@gmail.com">smarko@gmail.com</a>> wrote:<div><span class="gmail_quote"></span><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
I'm aware of this, but there can be situations where script can not be
allowed to continue, before certain "stuff" has been done for sure.</blockquote><div>
Synchronous ajax calls freeze the entire *browser* until completed, not just the current script, whereas asynchronous calls do not. Google "ajax synchronous" for better info on why this is not desirable behaviour.
Chris
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Here's a great blog post from Doug Crockford, one of the gods of Javascript on the subject:
""""
Many people prefer to use it synchronously. When used this way, the
JavaScript engine is blocked until the interaction with the server is
complete. Because it blocks, the flow of control looks a lot like an
ordinary function invocation. Temporal complexity is abstracted away,
leaving a very familiar and comfortable programming pattern. It works
particularly well when the server is on the same machine, or nearby on
the <acronym title="Local Area Network">LAN</acronym>. Unfortunately,
it can perform very badly if the server is under heavy load, or if the
browser is connected to the server over a slow link. Because the
JavaScript engine is blocked until the request completes, the browser
will be frozen. The user cannot cancel the request, cannot click away,
cannot go to another tab. This is extremely bad behavior.
Fortunately,
XMLHttpRequest provides an option for asynchronous operation. When you
set the asyncFlag flag to true, the JavaScript engine does not block.
Instead the request returns immediately, with a potential action that
will be triggered later when the result on the request is known.
""""
Callbacks are your friend, and give you the same functionality as synchronous calls without the downside :)
Chris
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Chris Domigan