Questions About Memory Structure Of Value Types And Reference Types

Oct 12, 2006

JavaScript hides its memory structure.
I know that numbers, booleans, null and undefined are value types
(value is directed saved in a variable).

I want to know:

- How JavaScript distinguishes value types from reference types by
seeing the variable content?

- How many bytes are allocated in memory when I declare the following?
var i;

I can program in JavaScript without understanding them.
But I'm curious.

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Reference Input Types Separately (i.e. Text, Radio, Checkbox)

Jun 2, 2005

Does anybody know if it is possible to reference only text inputs, and not radio and checkboxes, and if so, how?

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Java Script Memory Management Questions

Jul 20, 2005

I'm trying to find out how JavaScript manages its memory. In
particular when using the 'new' operator to create an object is it
necessary to explicitly delete this object (before it moves out of scope,
like c++) or does JavaScript clean this up automatically?

What about string varaible which uses concatenation extensively?

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ChildElements - Get Only Certain Tag Types?

May 17, 2011

How do I get the childelements of a div, but only the child elements that are "ahref" tags?

for example:

<div id="someDivID">
<a href="somepath.html">link 1</a>
<a href="somepath.html">link 2</a>

[code]...

I want all the childElements under someDivID that are "a href" types...I am using prototype: I figured the following would work, but didn't.

$('someDivID').childElements.getElementByTagName('a')

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Function And Object Types

Jan 25, 2007

function aa() {};
var bb = new aa();

var dd = new function cc() {};

aa.prototype.rr = 100;
cc.prototype.rr = 100;

---------------------------------------------------------------

i wrote the code above that makes two functions and two object for
those.

bb(object)<-aa(function),
cc(object)<-dd(function).

i think it's all the same way to make an object for a function.

but if u try to debug,

bb object has rr right after "aa.prototype.rr = 100" statement
but cc deosn't have rr variable.

can anyone explain it why?

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2 Input File Types Need Same Value

Sep 22, 2011

<div class="wrapperAttribsOptions">

This pice of code is dynamically created by my shopping carts admin section which is an attribute for a certain product.

The problem I have is that all the attributes are displayed in an array and positioning each is not possible (well, I have posted a query in another forum with regards to that). I have taken the code, as viewed in the source code, and added it in where I please e.g. radio buttons, checkboxes etc, which function perfectly.

This does make 'duplicate' field but I have used display:none on the generated code which hides it. I have found a snippet of code which fixes issues will type=text fields....

But this can not be done when it comes to type=file.

Once you browse and select your image, i need the directory to be entered into the 'real' field for uploading when submitted.

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Restrict File Types

Feb 14, 2007

How do i restrict files types that can be accessed when using the input element type file...like the one used when uploading..how do i restrict it to certain files with given file extensions?

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JQuery :: TableSorter - Different Types Of Data?

Jul 21, 2010

I have a table where the first column is mixed with words and dollar amounts and by default, before you sort, it looks like this:

[Code]...

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List Of Event Types For Listeners?

Sep 9, 2009

Does anyone know where I can find a complete list of DOM/DHTML event types documented?

I'm trying to learn more about advanced event handling in JavaScript and I'd like to find lists of event types that I can attach/add event listeners to. I've been searching around and I've found a few resources, but nothing that seems complete.code...

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Typecasting Userdefined Types In Jscript

Jan 18, 2010

I have an activeXobject that I am using in Jscript. The object has a method which takes a structure and fills it with data. I have created the structure like . .

function MyStruct()
{
a = "aaa";
b = "bbb";
}

when I pass MyStruct to the method I get a type mismatch error!

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JQuery :: Cleaner Way To Add Classes To Various <input/> Types?

Sep 16, 2010

Since IE 6 doesn't recognize type selectors in css (input[type=xxx] {}) I'm adding classes to elements dynamically so I have handles for the different types of <input/> elements.Here's what I'm using, but it feels sloppy (maybe not the most efficient approach?). Is there a better/less verbose/more efficient way to do this?

$('input')
.filter('[type=text]').addClass('input_text').end()
.filter('[type=radio]').addClass('input_radio').end()

[code]....

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JQuery :: Find Multiple Object Types?

Jul 28, 2010

Can I find multiple objects in one call? For example, I have ahold of a TD object that has in it input and select objects. I want to addClass to both the input and select objects therein? Something like ".find('input || select')"? Otherwise I guess I could just do multiple calls similar to:

//First find all of the required elements indicated by the red *
$(
"span[class=redEmphasis]").each(

[code]....

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JQuery :: Selecting Different Types In Same Selector Does Not Work?

Nov 2, 2011

I'm wondering why I cannot use multiple input types in the same selector...

$("input[type!='radio'],input[type!='submit'],textarea","#mycontext")

with only one input[type..] works

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JQuery :: Show Text As User Types In Different Div?

Jan 20, 2011

Basically I have an text field with an id of s_username As the user types I want to append this to a var so I can display what the user has entered at the side of the screen, I have been using this for select boxes:

var ramCost = $("#ram").val();

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Auto Suggest Of Words As A User Types

Mar 23, 2011

what I want to do is have an auto suggest of words as a user types, the code that I have works only once.For example: if you type.. hel, it will suggest hello but once you press space and type hel, again it doesn't suggest hello, I need it to suggest words even after you press space.

HTML

Code:
<div>
<h3>Auto Suggest</h3>
<input type="text" size="30" value="" id="inputString" onkeyup="lookup(this.value);" onblur="fill();" />[code]....

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Text Box In Which User Can Enter Only 4 Types Of Values

Sep 20, 2010

I need help with javascript regular expressions.I have a text box in which user can enter only 4 types of values.

1) Varchar(n) where 0 < n <=80. Ex: Varchar(20)
2) Char(n) where 0 < n <=80. Ex: Char(20)
3) numeric(x,y) where x>y and 1<= x <=35 and 0<= y <=15. Ex: numeric(20,6)

If the text box value doesnot match this pattern, we should throw him alert message.

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Form Input Types Not Working With Script

Nov 9, 2010

I am trying to add radio buttons in this quiz script that i'm using, but when i change the drop down box to radio buttons the quiz script stops working, i.e it will not calculate the correct answers / percentage.

I dont think i am correctly adding the input type "radio" and the script cannot recognise the value properly as i'am trying to make custom radio buttons from javascript / css.

Here is the script thats stopped working but how do i make the radio buttons send the correct value to the quiz script?

<HTML>

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Change What The User Types In A Text Field?

Mar 20, 2011

I'm trying to change what the user types in a text field if they hit a certain key combination. For example, "cx".

This code checks for the letter "x" to be pressed, then checks to see if the second to last letter is the letter "c". If it is, then it deletes the letter "x" and replaces the "c" with the letter "ĉ".

Code:
// This code checks for a certain keypress combo. For example cx, Cx, gx, Gx, etc...
// The hard to type esperanto characters we aim to insert.
var esperanto_c = "ĉ";

[Code].....

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JQuery :: Select All Input Text Types Not Having Class Already?

Sep 23, 2010

I have a form that has a bunch of text inputs, and I would like to select all that don't already have a class "errorClass" assigned to them. My JQuery currently is:
$('input[type="text"]').addClass("idleField");
But that adds the class "idleField" to ALL text fields, overriding the ones that already had the class "errorClass" assigned to it. What is the proper syntax to add the "idleField" class to all text inputs that don't have the "errorClass" assigned?

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Change Div Opacity - Allow A User To Filter The Types Of Projects

Nov 28, 2011

I'm adding a sub menu to my portfolio page that will allow a user to filter the types of projects they want to see, but I'm not really sure how to approach this. I have a variety of web design and motion graphics projects all on the same page, and I want the user to be able to "uncheck" one category or the other, and when they do, all the divs for the unchecked category will fade out. This is the page: [URL] Does that make sense? What I'm thinking of doing is applying a unique ID to the different categories, then build a little JS that will change the opacity of those specific IDs somehow. I am not a JS ninja though, and I'm thinking there is probably a more efficient way.

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Autofill File Form - Fill Certain Types Of Forms

Jun 22, 2010

struggling with figuring out how to fill certain types of forms. Here's a SMALL SNIPPET of a form. Parts of it would be VERY convenient if it could be automatically filled when page is loaded. Autofilling text boxes is easy enough. But I need the file box to be auto-filled with "C:/example.txt" when the page loads.

NOTE: typing value="C:/example.txt" does not work .

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JQuery :: Stripping All Types Of Style Before Displaying .load() Content

May 4, 2010

I'm making a quick and dirty Google Calendar displayer with help from Full Calendar and am struggling to display the details of each Google event correctly. As you may know, if you're not logged into Google Calendar, if you're given an event link or invitation you will be taken to a dynamically generated page displaying the basic details of that event. It includes a <link> ed stylesheet and inline style="..." for each element. I have attached a screenshot of a typical event page.

I'm trying to strip out all the style and just display the content:

eventClick: function(event) {
if (event.url) {
$("#details").hide().load(event.url);
$("#details *").each(function(){

[Code].....

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JQuery :: Submit Multiple Forms With Different Types, Values, And Actions?

Sep 16, 2009

How can I use jQuery to submit multiple forms with different types, values, and actions? For example:

Code:

<form name="form1" method="get" action="submit1.php">
<input name="value1" type="text" value="">
</form>[code]....

Can I start the jQuery process from within a function when clicking on the submit button?

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Testing Data Types Accross Multiple Function Parameters?

Aug 20, 2010

So I have a function, and in that function there are two paramaters: index and newLocation. Each of these parameters can initially either be an integer or a string: The string can only be the values of "first" or "last". I can do a long set of code for both parameters, but I was wondering if there was a way to iterate through the parameters to make the code more compact and reusable.

if(parseInt(index, 10) == "NaN")
{
if(index == "first")
{
//The first index of the array
index = 0;

[Code]...

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JQuery :: Highlighting/changing Text Color In A Textbox As User Types?

Sep 29, 2010

1) search the database for the words user is typing in the text box. This will happen with each key press.2) if there is a match - I need to change the text color.

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Ajax :: Combobox Autocomplete - When The Client Types On The Drop Down, The Records Appear From MySQL Database?

Apr 14, 2010

I am looking for an Ajax combobox (drop down, not a text box) auto complete script. I searched for it on Google and only result which seems similar to what I am looking for, is dhtmlxCombo. And that one is too complicated for me. What I basicly need is:

When the client types on the drop down, the records appear from MySQL database and when the client chooses one and submits the form, I want the ID (not the text written) to be posted.

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