Ways to access a JavaScript Object's Property in IE6 - javascript

I have a JavaScript object with some properties. Lets say:
var haystack = {
foo: {value: "fooooo"},
bar: {value: "baaaaa"}
};
Now, I want to access one of those properties, but I don't know which one. Luckily, this variable does:
var needle = "foo";
In modern browsers I seem to be able to do the following and it works:
haystack[needle].value; # returns "fooooo"
But in IE6 it throws a wobbly, haystack[...] is null or not an object.
Is there a way to achieve what I'm trying to achieve in IE6? If so, how so?
EDIT - Adding further information in response to the comments below...
What I am trying to achieve is actually related to CKEditor. I haven written a plugin image manager that opens in an iframe.
What I then want to achieve is to place the chosen image back in the correct instance of CKEditor (and there can be more than one instance on some pages).
What I have done (and I know this is an ugly hack), when the iframe is opened I have put a hidden field next to it with the name of the instance. So the parent page contains some markup like this:
<iframe><!-- Image manager --></iframe>
<input type="hidden" id="ckinstance" value="article_body" />
So then, inside the iframe when an image is selected to be inserted I have some JavaScript that looks like this:
var CKEDITOR = window.parent.CKEDITOR;
var instance = window.parent.$('#ckinstance').val();
var img = '<img src="/whatevers/been/selected" />';
CKEDITOR.instances[instance].insertHtml(img);
window.parent.$.modal.close();
This works fine in FF, Chrome, etc. Just IE6 is complaining with:
CKEDITOR.instances[...] is null or not an object.
EDIT 2
I've just done some debugging and actually it looks like IE6 is failing on window.parent.$('#ckinstance').val() and is returning undefined.
So the original problem that I've described is not the problem at all.
Still need help though :)

It's quite annoying when you spend a couple of hours scratching your head over something, only to realise the solutions is:
Tools > Internet Options > Delete Files

Related

Can't access object in jquery (prevObject?)

A function in my WP plugin has just randomly (as far as I can tell) stopped working.
Here's the code in question:
window.send_to_editor = function(html) {
var classes = jQuery('img',html).attr('class');
var items = classes.split(" ");
... more stuff here
}
I've confirmed that the html variable is indeed an img html tag. Here's what firebug shows when I do a console.log of the object (console.log(jQuery('img',html));):
Object[]
context -> undefined
jquery -> "1.11.2"
length -> 0
prevObject -> Object[img.alignnone.size-full.wp-image-1234 name.jpg]
And the error it shows is classes is undefined.
I figure there's something wrong with the object I get, but this used to work recently and I'm not aware of any changes in the site that could have caused this.
I'd appreciate any input on this.
EDIT:
More info. This happens with two plugins which are supposed to be unrelated (made by different people). It happens when, after uploading an image to the server (or selecting a previously uploaded picture) you try to insert it into the post.
As I said before this error has appeared out of nowhere, it was working as intended a couple days ago. The only thing I can think of that has changed since then is the domain name, but I can't see how that could be related.
The jQuery selector always returns a jQuery object, but when the length is 0 then no elements were found matching the selector that you provided. In your example you've confirmed that nothing is selected as the length of the jQuery object is 0. Perform a check whether an element was selected like this:
var $els = jQuery('img',html),
classes;
if ($els.length) {
classes = $els.attr("class");
}
Keep in mind that your DOM query is limited by what you pass in as the html parameter. If you simply want to find the images on the page do: var $els = jQuery('img');
I finally managed to fix this; the key was parsing the html string variable into proper HTML, using jQuery.parseHTML(). Thanks to everyone who helped!

Passing Javascript Object to Function & changing text field

This is probably a stupid mistake that i have made; i am still new to web development so be nice please :)
Here i create the object
var crs0 = {ID:1, TITLE:"test", DESC:"aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",ER:"a",LENGTH:"a", FEE:"a"};
Here i use an onclick event to call a function & pass the object as a parameter
<div class = "btnDC" onclick="display(crs0)">test</div>
Here is the function that i use to replace data in some textarea's & text inputs with properties from the object.
function display(crs)
{
document.getElementById("ttl").value=crs.TITLE;
document.getElementById("dsc").value=crs.DESC;
document.getElementById("er").value=crs.ER;
document.getElementById("lng").value=crs.LENGTH;
document.getElementById("fees").value=crs.FEE;
document.getElementById("ID").value=crs.ID;
}
The onclick does nothing & i have no idea why. (Other javascript on the page does work so i haven't missed a semi-colon :D )
[Update 1]
All of the data is pulled from a database the code above is copied from the page it produces; i have done a few tweaks & i can get it to produce an alert box for the display function however if i try & make it show any data of the object within that alert box it doesn't display anything (i hate not having a debugger), which suggests that the object isn't being passed.
Here is the PHP code i use to create the onclick
echo '<div class = "btnDC" onclick="display(crs'.$n.')">'.$inf['TITLE'][$n].'</div>
Could that be the issue?
it produces this line of code
<div class = "btnDC" onclick="display(crs0)">test</div>
As mentioned the code i have shown works (thanks juvian);
I generated this code from php & although the javascript generated was correct there was a problem with some of the php, i didn't find the exact problem but i have re-written most of the php & now it works.
As mentioned the code i have shown works (thanks juvian); I generated this code from php & although the javascript generated was correct there was a problem with some of the php, i didn't find the exact problem but i have re-written most of the php & now it works.

Adding Javascript variables to HTML elements

So, I have some code that should do four things:
remove the ".mp4" extension from every title
change my video category
put the same description in all of the videos
put the same keywords in all of the videos
Note: All of this would be done on the YouTube upload page. I'm using Greasemonkey in Mozilla Firefox.
I wrote this, but my question is: how do I change the HTML title in the actual HTML page to the new title (which is a Javascript variable)?
This is my code:
function remove_mp4()
{
var title = document.getElementsByName("title").value;
var new_title = title.replace(title.match(".mp4"), "");
}
function add_description()
{
var description = document.getElementsByName("description").value;
var new_description = "Subscribe."
}
function add_keywords()
{
var keywords = document.getElementsByName("keywords").value;
var new_keywords = prompt("Enter keywords.", "");
}
function change_category()
{
var category = document.getElementsByName("category").value;
var new_category = "<option value="27">Education</option>"
}
remove_mp4();
add_description();
add_keywords();
change_category();
Note: If you see any mistakes in the JavaScript code, please let me know.
Note 2: If you wonder why I stored the current HTML values in variables, that's because I think I will have to use them in order to replace HTML values (I may be wrong).
A lot of things have been covered already, but still i would like to remind you that if you are looking for cross browser compatibility innerHTML won't be enough, as you may need innerText too or textContent to tackle some old versions of IE or even using some other way to modify the content of an element.
As a side note innerHTML is considered from a great majority of people as deprecated though some others still use it. (i'm not here to debate about is it good or not to use it but this is just a little remark for you to checkabout)
Regarding remarks, i would suggest minimizing the number of functions you create by creating some more generic versions for editing or adding purposes, eg you could do the following :
/*
* #param $affectedElements the collection of elements to be changed
* #param $attribute here means the attribute to be added to each of those elements
* #param $attributeValue the value of that attribute
*/
function add($affectedElements, $attribute, $attributeValue){
for(int i=0; i<$affectedElements.length; i++){
($affectedElements[i]).setAttribute($attribute, $attributeValue);
}
}
If you use a global function to do the work for you, not only your coce is gonna be easier to maintain but also you'll avoid fetching for elements in the DOM many many times, which will considerably make your script run faster. For example, in your previous code you fetch the DOM for a set of specific elements before you can add a value to them, in other words everytime your function is executed you'll have to go through the whole DOM to retrieve your elements, while if you just fetch your elements once then store in a var and just pass them to a function that's focusing on adding or changing only, you're clearly avoiding some repetitive tasks to be done.
Concerning the last function i think code is still incomplete, but i would suggest you use the built in methods for manipulating HTMLOption stuff, if i remember well, using plain JavaScript you'll find yourself typing this :
var category = document.getElem.... . options[put-index-here];
//JavaScript also lets you create <option> elements with the Option() constructor
Anyway, my point is that you would better use JavaScript's available methods to do the work instead of relying on innerHTML fpr anything you may need, i know innerHTML is the simplest and fastest way to get your work done, but if i can say it's like if you built a whole HTML page using and tags only instead of using various semantic tags that would help make everything clearer.
As a last point for future use, if you're interested by jQuery, this will give you a different way to manipulate your DOM through CSS selectors in a much more advanced way than plain JavaScript can do.
you can check out this link too :
replacement for innerHTML
I assume that your question is only about the title changing, and not about the rest; also, I assume you mean changing all elements in the document that have "title" as name attribute, and not the document title.
In that case, you could indeed use document.getElementsByName("title").
To handle the name="title" elements, you could do:
titleElems=document.getElementsByName("title");
for(i=0;i<titleElems.length;i++){
titleInner=titleElems[i].innerHTML;
titleElems[i].innerHTML=titleInner.replace(titleInner.match(".mp4"), "");
}
For the name="description" element, use this: (assuming there's only one name="description" element on the page, or you want the first one)
document.getElementsByName("description")[0].value="Subscribe.";
I wasn't really sure about the keywords (I haven't got a YouTube page in front of me right now), so this assumes it's a text field/area just like the description:
document.getElementsByName("keywords")[0].value=prompt("Please enter keywords:","");
Again, based on your question which just sets the .value of the category thingy:
document.getElementsByName("description")[0].value="<option value='27'>Education</option>";
At the last one, though, note that I changed the "27" into '27': you can't put double quotes inside a double-quoted string assuming they're handled just like any other character :)
Did this help a little more? :)
Sry, but your question is not quite clear. What exactly is your HTML title that you are referring to?
If it's an element that you wish to modify, use this :
element.setAttribute('title', 'new-title-here');
If you want to modify the window title (shown in the browser tab), you can do the following :
document.title = "the new title";
You've reading elements from .value property, so you should write back it too:
document.getElementsByName("title").value = new_title
If you are refering to changing text content in an element called title try using innerHTML
var title = document.getElementsByName("title").value;
document.getElementsByName("title").innerHTML = title.replace(title.match(".mp4"), "");
source: https://developer.mozilla.org/en-US/docs/DOM/element.innerHTML
The <title> element is an invisible one, it is only displayed indirectly - in the window or tab title. This means that you want to change whatever is displayed in the window/tab title and not the HTML code itself. You can do this by changing the document.title property:
function remove_mp4()
{
document.title = document.title.replace(title.match(".mp4"), "");
}

Reasons a variable can be undefined on iPad vs. being defined in my Browser?

I'm clueless.
In my Jquery Mobile Plugin I'm declaring:
var $currentEntry = $.mobile.urlHistory.stack[$.mobile.urlHistory.activeIndex].url;
$activePage = $('div:jqmData(url="'+ $currentEntry +'")');
So I'm taking the active page's url and use it to construct an $activePage object.
This works fine on desktop, but on my iPad (iOS3.3), $currentEntry is defined correctly, but $activePage is undefined.
Question:
What can be reasons for this?
You can rule out race conditions, because wrapping this in a 10sec timeout still produces the same result. Also, if I console the respective page directly and query it's data-url, it shows the correct value. So how come the above still gives me undefined on iOS
undefined
while working correctly everywhere else?
Thanks for any hints!
EDIT:
The element will be dynamic, but I can console for the page in my setup directly like so:
console.log( $('div:jqmData(wrapper="true").ui-page-active').attr('id') );
console.log( $('div:jqmData(wrapper="true").ui-page-active').attr('data-url') );
Both return the correct id and data-url, so the elements must exist.
EDIT2:
I can query for the attribute data-url which gives me the correct value. However, I cannot select using this attribute like so:
$('div[data-url="'+$currentEntry+'"]').length
which gives me 0
I am going to admit that I am blind-guessing, but you should try:
$activePage = $('div').filter(function(){return $(this).jqmData('url') === $currentEntry})
BTW, just for semantics i think "$currentEntry" shouldn't start with a dollar sign if it is not a jQuery object.

This javascript works in every browser EXCEPT for internet explorer!

The webpage is here:
http://develop.macmee.com/testdev/
I'm talking about when you click the ? on the left, it is supposed to open up a box with more content in it. It does that in every browser except IE!
function question()
{
$('.rulesMiddle').load('faq.php?faq=rules_main',function(){//load page into .rulesMiddle
var rulesa = document.getElementById('rulesMiddle').innerHTML;
var rules = rulesa.split('<div class="blockbody">');//split to chop off the top above rules
var rulesT = rules[1].split('<form class="block');//split to chop off below rules
rulesT[0] = rulesT[0].replace('class=','vbclass');//get rid of those nasty vbulletin defined classes
document.getElementById('rulesMiddle').innerHTML = rulesT[0];//readd the content back into the DIV
$('.rulesMain').slideToggle();//display the DIV
$('.rulesMain').center();//center DIV
$('.rulesMain').css('top','20px');//align with top
});
}
IE converts innerHTML contents into upper case, so you probably are not able to split the string this way, as string operations are case sensitive. Check what the contents really looks like by running
alert(rulesa);
Andris is right. And that's not all. It'll also throw away the quotes in attributes.
It is completely unreliable to make any assumptions about the format of the string you get from innerHTML; the browser may output it in a variety of forms — some of which, in IE's case, are not even valid HTML. The chances of you getting back the same string that was originally parsed are very low.
In general: HTML-string-hacking is a shonky waste of time. Modify HTML elements using their node objects instead. You seem to be using jQuery, so you've got loads of utility functions to help you.
In any case you should not be loading the whole HTML page into #rulesMiddle. It includes a load of scripts and stylesheets and other header nonsense that can't go in there. jQuery allows you to pick which part of the document to insert; you seem to just want the first .blockbody element, so pick that:
$('#rulesMiddle').load('faq.php?faq=rules_main .blockbody:first', function(){
$('#rulesMiddle .blockrow').attr('class', '');
$('.rulesMain').slideToggle();
$('.rulesMain').css('top', '20px');
});
My IE debugger throws an error on your script when I click that button. On this line:
var rulesT = rules[1].split('<form class="block');//split to chop off below rules
IE stops processing the Javascript and says '1' is null or not an object
Don't know if you solve it, but it work's on my Ugly IE ... (its an v8)
Btw: It's me, or does pop-up widows wen open are really, really, really slowing down that platform ?

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