Does Order Of Logic Comparisons Affect Speed In The Same Statement

Mar 18, 2010

was wondering if it made sense to optimize the comparison order inside an if() statement if one of the comparison targets is a function call eg:

var a = true,
b = function() {return false;};
if (b() || a) {...}
if (a || b()) {...}

would the second statement run faster because it would theoretically never need to call b() in this situation? can the eval order be relied on? does this depend on the js engine/internal optimizations?

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Screen Updates Don't Match Program Logic/state Or Order

Jul 20, 2005

there's a line in my Javascript program that makes a change in the
appearance of an area of the screen. it is a game program, so there are
a cascade of changes after the user makes a move. these are carefully
sequenced and timed in a loop which contains the "action" statement

document.images[k].src = offGIF[currNode];

unfortunately, the *actual* screen updating appears to be 1)
asynchronous and 2) faulty!

_asynchronou_s in that things change in the wrong order, as if each has
its own thread and they run at random.

_faulty_ in that occasionally an area that would change from, say,
picture1.gif to picture2.gif and back again (according to game logic)
lands up showing picture2.gif. even though the internal game logic has
it recorded (and i assume document.images[k].src would be correct, even
though the screen is not) as picture1. so.

is there a way to wait or surrender control to the system until the
program statement's intent has actually been rendered to the screen?
something i can test to see if the unerlying system mechanism has caught
up with all changes to document.images?

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Two Not Equal Comparisons In An OR Condition?

Nov 5, 2009

Could anyone tell me (or link me to some place that can) why the following if-statement will execute?

if (5!=6 || 7!=8) {
alert("Why does this work?");
}

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Resolved Array Comparisons Is Always True When It Shouldn't Be

Apr 15, 2009

I have a small textfield input and submit button. The user is required to input the prefix of their UK postcode and a dialogue boxpopsup saying basically yes or no. My problem is I have an array of postcodes, but if for example someone in Liverpool entered their postcode as L1 1AA, it would say 'yes' but if their mate who enterd in L12 1AA, it would still say 'yes' but it should say 'no'. L1 should be true and L12 should be false. Also to mix things up a bit. I have now been asked to creat a third 'if',if a user enters a code of JE (and then any suffix after ie. 1, 2, 3, 4 etc.), could this be made to say 'unavailable' or some sort.

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Date Comparisons Not Taking The Year Into Consideration

Aug 29, 2005

I am having problems while sorting my report on the date column.

It sorts on the day and month but does not sort on the Year

for ex.
if I sort on the date i get the following results: (mm/dd/yyyy)
01/03/2004
01/04/2004
01/05/2003
01/06/2003
01/07/2004

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IE Reverses Logic

Jul 23, 2005

While the following code works in Firefox and Mozilla,
IE6 reverses the logic (when I click yes on the top it checks no on the
bottom and vice versa).

<form method="POST">
<p>
<input type="radio" name="decide" value="yes"
onchange="decide1[0].checked = decide[0].checked">yes
<input type="radio" name="decide" value="no"
onchange="decide1[1].checked = decide[1].checked">no.</font></p>
<p>
[...]</p>
<p>
<input type="radio" name="decide1" value="yes"
onchange="decide[0].checked = decide1[0].checked">yes
<input type="radio" name="decide1" value="no"
onchange="decide[1].checked = decide1[1].checked">no.</p>
<p>
<input type="submit" value="Submit"><input type="reset"
value="Reset"></p>
</form>

Please advise.

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If Statement Returning False On A True Statement?

Apr 4, 2011

my webstie allows users to change the color of the background, so to keep the text readable I have it changing as well.the color picker I am using has text boxes with rgb values 0-255 for each.I am trying to get one bit of text to alternate between red and blue with the conditions

Code:
if(blue>green && blue>red)
{

[code]....

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Locally Var.s Affect Global Ones

Sep 7, 2005

Say I have script that looks a bit like this:

Array.prototype.getValue = function(ind, dir) {
if (dir !=0) ind[ind.length-1] += dir;
// more script
}

screens = [...// a big array
fnd = [1,2,3];
// 1.
a = findStart(fnd);
// 2.
b = findEnd(fnd);

findStart = function(cs) {
return screens.getValue(cs, 1);
}

findEnd = function(cs) {
return screens.getValue(cs, -1)
}

As I go from 1. to 2. the value of fnd changes. I don't understand how a
locally scoped variable might be affecting a global one.

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Paging Logic In Javascript?

Apr 12, 2007

I have writting all of my paging logic in javascript.
It works pretty fine. Basically, I have created a
gridview with full paging in javascript. Now, given
a certain need, I am being advised to do my paging
on the server.

My question: is there a performance cost by doing
all my paging server-side (and cost benefit by keeping
it on the client). Or, does it matter?

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JQuery :: How To Affect DIV Inside Other One

Oct 25, 2010

I don't know how to select an element inside other elements, like div's. I have my html site like this:
<div id="container">
<div id="top"><h3>Title</h3</div>
<div class="desc">
Lorem Ipsum dolor set...
</div></div>
<div id="container">
<div id="top"><h3>Title</h3</div>
<div class="desc">
Lorem Ipsum dolor set...
</div></div>...so on...

I want to click on any h3-tag and the jquery should open the next div with class desc. At the moment I use this script:
$(document).ready(function(){
$('.desc').hide();
$('h3').click(function() {
$(this).next('.desc').toggle(400);
return false;
});
});
I absolutly dont know what to change inside the script to affect the next div with class desc.

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OnLoad And Onchange Affect Each Other

Mar 15, 2009

I'd like to ask why the onLoad and onchange affect eachother ? How i can avoide that?

<body onLoad="checkCookie()">
and
<select name="province_state_territories" id="state" onchange="setCities();">

when i use the above at the same time, the search function have not another option to choise. It means the option for selection have not values. Because i want to use the "<body onLoad="checkCookie()">" to check my cookie and decide which Language i will use.

[Code]....

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Jun 9, 2011

[URL] You see those social network icons under the product description div? When the mouse rolls over the right edge I want a drawer affect that pulls the icons into view and lets the user click one of the social links. When the user rolls his mouse away from the section, the drawer should return to its position.

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Jun 12, 2011

I want to create an image gallery like imageflow, but having tough time to figure out the way top, left, height and width are computed for each animation call.

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Script To Only Affect A Certain Section Of My Page

Apr 4, 2009

I need a JavaScript script to only affect a certain section of my page. Is it possible that I could put that part of my page in a DIV or a FRAME to get this to work? How would I do this?

Here is my script:

As you can see, that would choose a random link from my entire page. If I want to make it choose from a section of my page, what would I do? (there are a lot of links on this page, and I don't want to assign number to each and every one of them, and then choose a random number)

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Using The DOM To Affect A Form Element's Label

Aug 7, 2004

I have a form that is validated using the DOM. If a user attempts to submit this form before completing all required fields the fields turn red. The only drawback to this is the reading the text in the fields can become difficult. One thing I was hoping to do was to have the text associated with each form element turn red insteadof the field.

Each form element's text is enclosed in a <label> tag and I figure setting that tag's font color to red would be easy enough to do...if I knew how to reference it. That's the thing, I'm not sure how to reference it.

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Moving Server Side Logic To Javascript..

Feb 12, 2007

I work for a financial company. I am planning to give a presentation
to rest of the development team (15 people) here on moving server side
logic to client-side javascript for an internal intranet application
rewrite. This approach will definitely stir up hot debate from
hardcore server-side Java folks who wants to do UI stuff even on the
server!. Since I am pretty much known as the JS or UI Guy of the
group, my Boss wants to hear the broad spectrum of PROs/CONs from each
proponent.

Personally, I think Javascript/Ruby is a more productive language than
Java.

My idea is simple. It is to convert most business logic to client-
side javascript and have calls to server-side code restricted to user
roles with data validation. Thats as simple as it gets.

Here are my list of arguments

1. True separation of UI logic from server-side data processing code
(no more server code spitting out client-side code)
2. Better user experience with faster response
3. The whole web 2.0 thing (no page refresh) :)
4. Offload client processing from server therefore reducing network
traffic (not really a strong argument is this?)

Keep in mind this is an internal app. Even if someone figures out the
JS logic behind the page and try to hack the app by posting to
Servlets, they will be restricted by their login role, and data
validation will take care of any bogus data being submitted.

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Jul 5, 2010

[code]I'd like to click FirstDrilldown and have it display div#SecondDrilldown. Then I'd like to be able to click SecondDrilldown to fire off a different click handler. The problem is that the click handler bound to the FirstDrilldown intercepts the click. I'm fairly sure I could bind and unbind the click FirstDrilldown click event but that's kind of an inelegant solution.Is there just a way to just promote the SecondDrilldown click event to have a greater precedence than the one associated with FirstDrilldown?

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JQuery :: Affect One Element Out Of Many Identical Elements?

Jan 18, 2011

I would like to ask if the following is possible.

1) I have one hundred identical links on my page
2) I have a function that changes a clicked link to "display: none" (using the toggle functioon)

Is it possible for me to set it up so that only the link that is clicked (that is, only one element) gets affected? I don't want to click and have all the links disappear.. just the one that was clicked.Would this code below work in all browsers? [code] And secondly, may I ask whats the difference between $("a") and $('a'). I've seen people use single quotation makrs and double. Which is better ??

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Logic Error In AcroJS - Subtracting Instead Of Toggling

Feb 4, 2011

Putting some javascript into a pdf file and can't get this to work out right.

Basic setup:

Field X = checkbox;
Field Y = numeric input field;

Here's what should happen (increment is toggled):

Y has a value. When X is checked, Y is increased by 5. When X is unchecked, Y goes back to its original, unmodified value.

Here's what really happens (increment is subtracted):

Y has a value. When X is checked, Y is reduced by 5. When X is unchecked, Y is reduced by 5 again. Anytime X is clicked on, Y is reduced by 5 yet again.

Here's the code:

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Feb 26, 2011

How to create a function that would allow me to add to or subtract from a maxvalue, and thankfully I got help regarding that. However, something's got me stumped for the past few weeks that I still can't resolve...

This is the relevant code:

As it stands, it works as long as the total value is less than or equal to the limit (for advantages it's 15, for disadvantages it's 10). However, the moment it goes past the limit -- for instance, if you change Antisocial's value from 2 to 7, or if you add several additional checkboxes with any values -- the whole thing starts going crazy; specifically, maxvalue doesn't revert to 40 when the all the checkboxes are unchecked.

What I'd want to happen is that the user cannot select or apply advantages or disadvantages if the maximum advantage is greater than 15 or the maximum disadvantages is greater than 10.

I'm thinking that a button for adding disadvantage points to/subtracting advantage points from the maxvalue (that becomes disabled if the user goes past his limit on advantages/disadvantages) is useful at this point, but I'm really stumped on the implementation of the idea. An alternate idea of mine is that all other advantage/disadvantage checkboxes would become disabled if their value is greater than the remaining number of points, but I don't know how that is possible either.

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Parent.appendNode() Not Taking Affect Until End Of Function?

Nov 22, 2009

I'm developing a site in HTML 5 and SVG, just for the heck of it. I have a portion of the site that uses the <embed> tag to load a new SVG when you change pages, which, in theory, would let me do effects between pages. However, no matter what I try, there is a white flash as the new SVG is loaded into the page. So, I figured I would make the embedded area invisible until it loaded, which was no big deal. But when I tried it, the flash still happened! So, I built a pause function to wait a bit longer. It sill flashes. Anyway, 7 hours later, I've determined that the newly embedded page isn't actually being downloaded and embedded until the end of the changePage() function is reached.

Here's my java script:

var close1;
var close2;
var bar;
var svgLoaded = false;

[Code]......

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Scriptaculous Effects Affect Inline Styles Only?

Apr 26, 2010

Not a huge issue, more of an annoyance, but when firing

Code:
Effect.Appear('whatever');

it only works when

Code:
display:block;

is an inline style on the target element and not when it's applied via an external style sheet. Is there a fix for this or is it just a quirk of the library?

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Apr 1, 2011

I'm trying to generate lists for each week (open in IE to see what I mean) but somehow one row is being missed and I can't seem to figure it out.

Link to ZIP is below: [url]

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Feb 5, 2011

I have 3 images that I would like to display horizontally. I need a default text to appear first when the page loads. When an image is clicked on, the new text should slide down covering the default text. When another image is clicked on that text should slide down and cover the previous image's text.Right now the script only allows a vertical display of the images and I can't put the sliding text in a specific place.Here is the CSS

Code:
<head>
<style type="text/css">

[code]....

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Affect The Websites Rankings In Search Engines

May 26, 2009

i want to know about the use of java script codes in website. How will this affect the websites rankings in Search Engines. what are the advantages and disadvantages of Using javascript codes in websites.From SEO point of View.

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JQuery :: Select Elements With Multiple Classes AND Logic?

Apr 13, 2010

The default behaviour for a class selector is: "An element can have multiple classes; only one of them must match." Is there a class selector where you can use multiple classes and all of them have to match?

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