jQuery UI：如何打开对话框

I jsut checked the sample of jQuery UI that opens a dialog, it's strange that the message needs to be written in HTML and read it by jQuery selector:

http://jqueryui.com/demos/dialog/

 <script>
 $(function() {
  $( "#dialog" ).dialog();
 });
 </script>



<div class="demo">

<div id="dialog" title="Basic dialog">
 <p>This is the default dialog which is useful for displaying information. The dialog window can be moved, resized and closed with the 'x' icon.</p>
</div>

What I want to do is quite simple, I want the dialog to display a string defined as a js variable, like this:

var cmd_str = "abcdefg";
$(cmd_str).dialog();

But this doesn't seem to work well.

when you call $(cmd_str) jQuery searches for a tag named abcdefg... you should put the entire markup inside $(), then inject it into the DOM and then call .dialog(). Like that, I guess.

$("<div id=\"dialog\" title=\"Basic dialog\">"+
    "<p>This is the default dialog which is useful for displaying information."+
    "The dialog window can be moved, resized and closed with the 'x' icon.</p>"+
    "</div>").appendTo("body").dialog();

It cannot be just any string, it needs to be html.

var cmd_str = "<div>abcdefg</div>";
$(cmd_str).dialog();

or maby a cleaner version:

var cmd_str = "abcdefg";
$(cmd_str).wrap("<div></div>").dialog();

Further explanation:

$("abcdefg") would match a <abcdefg /> element as $("a") would match a <a /> element.

To destroy:

Easiest would be to save the jquery object used for the dialog in a variable like this.

var cmd_str = "abcdefg";
var $message = $(cmd_str).wrap("<div></div>").dialog();

function destroyMessage(){
    $message.dialog("destroy");
}

You have to have a div or some other element, make it hidden then the dialog will make it visible according to the dialogs .show and .hide functions. Use the .text or .val (depending on message element) functions to set your message.

<div id="dialogMsg" style="hidden"></div>
$("#dialogMsg").text("Your message").dialog().show();
// ... or it can be closed if settings are set when doing .dialog(...)
$("#dialogMsg").hide();