[code]how i can set context/scope for myStartAction so it can access (this.url) variable?console.log(dd.url) will work but i can't predict what name will object have (that depends on user) there might be more than one instance of myObject
View 10 RepliesI am running my website using Weblogic, so the path is something like
http://<myip>:<port>/<servername>/
On JSP pages I can use <%=request.getContextPath()%to get the root
path of the site, ie that specified above. How can I get the same using
Javascript?
For example, something like <a href='/home'>..</awill not work as
that would point to http://<myip>:<port>/home and needs to point to
http://<myip>:<port>/<servername>/home
Is it possible to access the parent context within $.post to asign the result to the parent selection?
See this code here:
$("a[href='country#']").click(function(event) {
var dieBusinessUnit = 'THIS VAR SHOULD CONTAIN RESULT OF $("businessunit", xml).text())';
[Code].....
If I do . . .
myForm=document.tstForm;
function initialSetup(){
myForm.fld01.value="Test 01"
myForm.fld02.value="Test 02";
myForm.fld01.focus();
}
Then, in the body tag, I do onLoad="initialSetup()",
the script doesn't work and I get a "myForm has no properties" error
I know it'll work if I move it within the function, but I figured a
global variable would retain its value within the function. Why not?
Given the following working code:
function attributes() {
var attr1 = arguments[0] || '_'
var attr2 = arguments[1] || '_'
return (
function (el1, el2) {
var value1 = el1[attr1] + el1[attr2];
var value2 = el2[attr1] + el2[attr2];
if (value1 > value2) return 1;
else if (value1 < value2) return -1;
else return 0;
}
);
}
var a = [
{ a:'smith', b:'john' },
{ a:'jones', b:'bob' },
{ a:'smith', b:'jane' }
];
a.sort(attributes('a', 'b'));
for (var i =0; i < a.length; i++) {
document.write(a[i].a + ', ' + a[i].b + '<br>');
}
My question is, are attr1 and attr2 guaranteed to exist through
the lifetime of a.sort(attributes('a', 'b'))?
As I understand it, the anonymous inner function reference I am
returning is a property of attributes(). As such, when I return a
reference to the anonymous inner function, the outer attributes()
function must continue to exist (as must attr1 and att2) until
there are no further references to the inner anonymous function.
As a result, there is no danger of attr1 or attr2 "disappearing"
during the repeated calling of the anonymous inner function.
Is my explanation basically correct, or am I deluding myself and
I'm just lucky that the garbage collector hasn't recovered attr1
or attr2 while the sort is still going on? In other words, is the
behaviour I'm seeing consistent and predictable, or should I
change my approach?
I think I've had JavaScript variable scope figured out, can you please
see if I've got it correctly?
* Variables can be local or global
* When a variable is declared outside any function, it is global
regardless of whether it's declared with or without "var"
* When it is declared inside a function, if declared with "var", it's
local, if not, it's global
* A local variable that is declared inside a function is local to the
whole function, regardless of where it is declared, e.g.:
function blah() {
for(var i ... ) {
var j ...
}}
i and j will both be visible within blah() after their declaration.
* the notion of "function" in this context also applies for this kind
of construct:
var myHandler =
{
onClickDo: function()
{
in the sense that whatever one declares inside onClickDo with "var"
will only be visible inside onClickDo. What else, am I missing anything?
I've created a jQuery script that uses a switch statement. However, my experience with it, relative to variable scope, doesn't seem to follow the logic.According to the JavaScript/jQuery theory, a global variable was accessible (meaning read & write) throughtout any function within any script (one that page).However, apparently that theory wasn't completely true as it pertained to switch statements that contained variables. To illustrate my case in point, I've included a simplistic version of my code:
$("#selector").delegate("div", "click", function(event) {
var testVar = 4;
switch (this.id) {
[code]...
As shown, the variable "testVar" is not accessible from one case to the next case .Furthermore, to add insult to injury, I am seeing the same behavior within the conditional if else statement counterpart to the switch statement.
I have this web application where users are able to fill out and submit reports. The reports and scripts are part of a whole system, that is, they are used on a couple of different clients written in both vb and c#. This is the web-version of those clients.The scripting language is javascript and is executed using different script engines on the different systems. But for the web-version it is just executed in the browser.The different fields in the report can be accessed by typing:ID1.value. To get ID1 to apply for the input-field with id ID1 I had to in the initfunction of the page write a window["ID1"] = document.getElementById("ID1");
But my problem is when this element change. Cause in the report I have a special element that in the browser is translated to a table-element with a report-field in each cell.When I switch the current row, I need to update the window["ID1"] to equal the correct report field on the selected row. But when trying to access the new variable ID1 from a buttons onclick event it is undefined.<input type="text" id="test" onclick="alert(ID1.value);" />What I think happens is that when the page is first drawn the onclick event is created and as I understand, variables inside an event has the same value as when the event was created.
So if ID1.value was something when the page was created it will be the same when it is called even if the value of ID1 is different. And that seems to be the case. When I debug the page, before entering the event, ID1.value has the correct value while inside the event it is undefined and after the event it has the correct value. If I write window["ID1"] correct value is also shown.But a weird thing is that in another place in the code I had the same problem but instead of having the code inside the onclick event I first had a global function changeActiveRow and inside that I had an eval, eval(document.getElementById("ID1_script")) where ID1_script is a hidden element whos value is a script using ID1.value and that works.
I am trying to convert some of my javascripts into a class and am
running into difficulties which i think are related to variable scope.
Basically I have a constructor function for a calendarInput class that
takes 4 parameters, the first is a reference name/number for this
input. I also have some functions for importing my PHP classes into
Javascript using AJAX (properties only. still trying to get methods
working but that's another story!). The relevant function is called
call_object_method(classname, methodname, createparams, methodparams,
post, callbackfunction). This creates an instance of the specified PHP
class using the parameters in createparams. It then calls the
specified method using the parameters in methodparams. The result is
passed back to the javascript function specified in the callbackfunction parameter (ie the value of xmlhttp.onreadystatechange is set to callbackfunction before xmlhttp.send() is called)
The function i am trying to fix is called show (x,y) which creates the
html for the calendarInput and displays it at co-ordinates x, y.
So, my code is as follows:
function calendarInput(calendarid, target, displaytarget, value)
{
this.calendarid = calendarid;
this.target = target;
this.displaytarget = displaytarget;
this.value = value;
this.show = function(x, y)
{
<!--// bunch of init and prepping code. includes creating
createparams and methodparams arrays //-->
call_object_method("cms_calendar", "getcalendarview",
createparams, methodparams, false, this.showcallback);
}
this.showcallback = function()
{
alert(this);
<!--//code to create html//-->
}
}
I know i've cut out most of the innards of this. This is because I
have already tested these functions and had the calendarInput working
outside of a class, hence am pretty sure that this is ok (plus it runs
to almost 1000 lines these days!!). My problem is that when I call the
show method, the alert on the first line of the callback function
returns the function showcallback instead of (as i was expecting) the
instance of the calendarInput object. Whilst this kinda makes sense I
can't figure out how to reference the Object instead. I have tried
'this.parent' but this returned undefined. I have tried changing the
way i reference the callback function (ie the final parameter of
call_object_method) but no joy.
I've recently started developing javascript using jQuery and so far I'm really enjoying it.Being a professional programmer (mainly C, C++, java and python) there is one thing that's been puzzling me regarding variable scope and unnamed function declarations. Let me exemplify:
------------------------
var sum = 0;
$(xmlobj).find("item").each(function(){
[code]....
I'm just starting out with Javascript as a development language and this will probably be a relatively simple problem for someone to solve for me.
I am trying to access a variable (this.bodyEl.innerHTML) from within a function but get an error message indicating that it is "undefined". I know that it is a valid variable because I call it elsewhere outside of the inner function itself.
I'm sure this is just a scope issue, but I'd welcome any suggestions on how to solve it with an explanation of where I've gone wrong if you have the time.
[Code]...
I think the last thing people seem to learn about in JavaScript when they're not coming from other programming languages is variable scope. Some even get all the way into AJAX without having learned about scope, and this is a time when it's really needed. Although the scope of JavaScript variables is non-complex by nature, it's something we should all get a full understanding for before we move too far.
Section 1: What is "scope"?
Section 2: The "var" keyword
Section 3: The "this" keyword
Section 4: Closures or "Anonymous functions and self-invoking closures
I am simply trying to use a global variable in javascript, but can only access the variable on the second call. I can't find anything that relates to this through my searches. My application is supposed to query the server for XML that tells me which years and months are available to put into combo boxes. I want to store this xml in a global variable to access it later.
[Code]....
I am using Ben Alman's JQuery resize plugin in order to obtain the varying computed width of an element when the window is resized (the element in question is a page wrapper that exhibits the expand-to-fit behavior of a block box, and it's computed width is obviously influenced by the resizing of the window. Essentially, what I need to be able to do, is to reference a variable that is defined in a .resize() function ('width_page') in a seperate .each() function.
[Code]...
I now understand that variables can't cross boundaries like in the example above, which leaves me a little stuck. I also understand that this is specific to the context of the .resize() function, and that it can't be taken out of it without using an element selector. Is there some way I can call the .resize() function in my .each() function?
Does any one know how to access variable from other function in jquery ?
View 8 Replies View RelatedI'm trying to populate a web page with javascript. I have 2 functions. One that runs on-load so I can populate a dropdown list. The second one to process the selection when the user selects an item from the list.
I have a global variable in the top of my javascript that I use in the functions and as long as I set it in it's global scope, everything works fine. But what I really want to do is to pass this into the javascript running on this page via the code...
My question is. Where do I put this code so that I can use it to set the global variable "weekNumber"?
I've tried putting this code in the populateList function - NOPE! I've tried referencing it via window.weekNumber and this.weekNumber - NOPE. I'm stumped.
I've spent far too many hours trying to understand this without success. Can anyone help me figure out where to put this code so I can set the global variable weekNumber?
Is there a better way to do this?
I got a simple plugin as below:
Code JavaScript:
$.fn.ajaxSubmit = function(options){
var submisable = true;
}
I want to to able to access the variable submisable from outside the plugin like doing something like below:
Code JavaScript:
$(function(){
$('form').ajaxSubmit();
$('div').click(function(){
[Code]....
I need to acsess an object property via variables, but don't get ahead.
Example:
var property = height;
"height" is a property of the object "flower". Now, I need a possibility to access "flower.height" with my variable property, means -->"flower.property" I tried everything like "flower.[property]" "flower.['property']" etc. but nothing did help.
I was wondering how to access parents class variable. For example:
Code:
function Class(){
this.variable; }
SubClass.prototype = Class;
SubClass.prototype.constructor = SubClass;
function SubClass(){
this.secondVariable = Class.variable; <-how to access parent variable?
}
I need little help with arrays :))
[Code]...
why I cannot access json data by using a variable as a node name. I'm trying to grab a random quote from a .json file and display it in a div. When I access a node in the object by node name I can access the node data. However, when I try to use a variable in place of the node name (because I want to grab a random node) I get an object undefined error.
JSON object:
{
"quote1" : {"quote" : "hello, world."},
"quote2" : {"quote" : "goodbye, world."},
"quote3" : {"quote" : "out of this world."}
[Code].....
I'm trying to access a variable that's set when the plugin is initialized. I'd also like to change that variable on the fly.
(function($) {
$.fn.plugin = function(options){
// default settings
var settings = {
[Code].....
In one of my functions I got the following lambda function. It works as intended, but I got a tiny problem. I'm trying to access the function-scooped variable "matched" and set it's value to "true". The problem is that it seems like the variable is existing as a local variable inside the lambda function, even if it's not declared inside the lambda function itself. So, the change "matched = true;" does not effect the variable that I declared.
Code:
//... code
var matched = new Boolean(false);
xmlhttp.onreadystatechange=function() {
if(xmlhttp.readyState == 4 && xmlhttp.status == 200) {
[Code].....
Well, it turns out IE8 has yet another problem. My code has a global variable (to the object) inside an object declaration that cannot be accessed by a function (that is also global).
The code is like so:
Code:
function myobject(params){
//public
this.initialize = function(){...}
//private
some variables...
//problem variable
var mouse = new Object()
mouse.x = 0;
mouse.y = 0;
//code...
slidecontainer = document.createElement("div");
slidecontainer.onmousemove = function(event) {
if(boo.isIE) {
e = window.event;
mouse.x = e.x + document.body.scrollLeft;
mouse.y = e.y + document.body.scrollTop;
} else {
e = event;
mouse.x = e.clientX + document.body.scrollLeft;
mouse.y = e.clientY + document.body.scrollTop;}}
//this function is in an interval
function moveslides() {
/* this is where I have the problem
It seems that the function doesn't recognize that mouse.x, or mouse for that matter, exists. Mouse is global to the object, so why can't this function access it?
*/if(mouse.x) {
code...
}}}
The page is at [URL] and works on every browser, including finnicky opera, except for ie. The full code is availabe when you right click and view the source on the page.
<script type="text/javascript" src="jquery-1.4.2.min.js"></script>
<script type="text/javascript">
var global_var = false;
function test_func() {
$.post("server.php", function(data){
alert("Data Loaded: " + data);
[Code]...
how would i build a multidimensional array? would it be: PHP Code:
var rinksAndPriceArray = new Array();
rinksAndPriceArray[0] = new Array();
rinksAndPriceArray[1] = new Array();
i've figured that out so far.
now, i want to be able to access a part of one of the arrays based on a variable that is passed into the function
the variable i'll send in will be the first part of the array ex: rinksAndPriceArray[0][0] and i'll want to return the rinksAndPriceArray[0][1] value.