I am trying to get the innerHTML of a hidden span. The JavaScript is from an iframe HTML page, and the hidden span resides in the parent page. A different function works when accessing contents of a list from the parent, but I can't seem to get at my span...
WORKS
document.getElementById(parent.genL[i]);
DOESNT WORK
document.getElementById(parent."span"+i).innerHTML;
- SyntaxError: missing name after . operator
The above line of code resides in a for loop and as it iterates through i it will grab data from each separate span. the hidden spans start at ID "span1" through upwards of 10-40k different hidden spans.
Anyways, I have a feeling that it has to do something with trying to concatenate the string int i. I assume i is an int anyways. Any thoughts? Thanks so much everyone!
Edit - Words, and added the innerHTML portion to the doesn't work line of code. Not sure if that will be making a difference or not...
Edit2 - Great answers everyone, learned some good syntactical tricks :) I simply moved the parent. portion to the front of the code as reccomend by the comment of mplungjan and the answer from Jacob T. Nielson. For some reason I still got the error using the brackets as suggested, but I will definitely tuck the brackets into my memory for future similar situations!
parent.document.getElementById("span"+i).innerHTML;
:)
Try changing it to an indexer.
document.getElementById(parent["span"+i]);
If the parent in the brackets is an object and you're trying to access something like parent.span1 then you need to use bracket notation instead of the dot.
document.getElementById(parent["span"+i]); should work fine.
I think what you are trying to do is get the i-th span element on the parent page. Correct?
You can do it like this
var s = parent.document.getElementsByTagName('span')[i];
s.innerHTML // <-- access innerHTML
Related
I am new to XPath and confused. Anyone can have a quick glance and see what is wrong in my syntax?
I'm trying to select all direct child div's of id="list-overview" which has two child nodes somewhere down their tree containing data-price<=20 and a div containing "Orange" text
let xy = $x(`//*[#id="list-overview"]/div[./div/a/div/div/div[#data-price<=20]][./div/a/div/div[#class='fruit'][contains(.,'Orange')]])`)
to break it up. I have tested these two separately and they worked.
`//*[#id="list-overview"]/div[./div/a/div/div/div[#data-price<=20]]`
`//*[#id="list-overview"]/div[./div/a/div/div[#class='fruit'][contains(.,'Orange')])]`
I just can't seem to combine them somehow and not sure what I'm doing wrong?
EDIT:
Tried the suggestions and the following xpath doesn't throw an exception anymore. But it returns empty Array while there are elements matching price < 20 and fruit="Orange"
$x(`//*[#id="list-overview"]/div[./div/a/div/div/div[#data-price<=20] and ./div/div/a/div/div[#class='fruit'][contains(.,'Orange')]]`)
If I understand your idea, you are missing the logical and between these 2 conditions. I corrected the XPath expression accordingly. Please try this:
let xy = $x(`//*[#id="list-overview"]/div[./div/a/div/div/div[#data-price<=20] and ./div/a/div/div[#class='fruit'][contains(.,'Orange')]])`)
UPD
Please try this:
let xy = $x(`//*[#id="list-overview"]/div[.//div[#data-price<=20] and .//div[#class='fruit'][contains(.,'Orange')]])`)
Instead of this
$x(//*[#id="list-overview"]/div[./div/a/div/div/div[#data-price<=20]][./div/a/div/div[#class='fruit'][contains(.,'Orange')]]))
You could do this to combine both of them,
to tightly couple both the child
$x(//*[#id="list-overview"]/div[./descendant::div[#data-price<=20]] and [./div/a/div/div[#class='fruit'][contains(.,'Orange')]])
or to either have one of them and still you would want to proceed further.
$x(//*[#id="list-overview"]/div[./descendant::div[#data-price<=20]] or [./div/a/div/div[#class='fruit'][contains(.,'Orange')]])
Also, I have included descendant to make it more readable.
Take this very simple example HTML:
<html>
<body>This is okay & fine, but the encoding of this link seems wrong.</body>
<html>
On examining document.body.innerHTML (e.g. in the browser's JS console, in JS itself, etc.), this is the value I see:
This is okay & fine, but the encoding of this link seems wrong.
This behaviour is the same across browsers but I can't understand it, it seems wrong.
Specifically, the link in the orginal document is to http://example.com?a=1&b=2, whereas if the value of innerHTML is treated as HTML then it links to http://example.com?a=1&b=2 which is NOT the same (e.g. If I created a new document, which actually had innerHTML as its inner HTML, and I clicked on the link then the browser would be sent to a materially different URL as far as I can see).
(EDIT #3: I'm wrong about the above. Firstly, yes, those two URLs are different; but secondly, the innerHTML which I thought was wrong is right, and it correctly represents the first URL, not the second! See the end of my own answer below.)
This is different from the issue discussed in question innerHTML gives me & as & !. In my case (which is the opposite to the case in that question) the original HTML is correct and it looks to me as if it is the innerHTML which is wrong (i.e. because it is HTML which does not represent what the original HTML represented).
(EDIT #2: I was wrong about this, too: it's not really different. But I think it is not widely known that & is the correct way to represent & inside an href, not just within body text. Once you realise that, then you can see that these are the same issue really.)
Can anyone explain this?
(EDIT #1+4: This only occurred to me a bit late, after writing my original question, but: "is & actually correct within the href text, and & technically incorrect?" As I said when I first wrote those words, that "seems very unlikely! I've certainly never seen HTML written that way." But however 'unlikely', or not, that is the case, and is the main part of what I wasn't understanding!)
Also related and would be useful, can anyone explain how to cleanly get HTML which does correctly represent the target of document links? You definitely can't just un-encode all HTML character references within innerHTML, because (as shown in the example I've used, and also as discussed in innerHTML gives me & as & !) the ones in the main run of text should be encoded, and just un-encoding everything would make these wrong.
I originally thought this was not a duplicate of innerHTML gives me & as & ! (as discussed above; and in a way it still isn't, if it's agreed that it's not as obvious or widely known that the same issues apply inside href as in body text). It's still definitely not a duplicate of A href in innerHTML (which somehwat unclearly asks about how to set innerHTML using JS).
Most browser tools don't show the actual HTML because it wouldn't be of much help:
HTML is often generated dynamically after page load with the help of CSS and JavaScript.
HTML is often broken and the browser needs to repair it in order to generate the memory representation needed for rendering and other stuff.
So the HTML you see is not the actual source but it's generated on the fly from the current status of the document, which of course includes all the fixed applied (in your case, the invalid HTML entities).
The following example hopefully illustrates all the combinations:
const section = document.querySelector("section");
const invalid = document.createElement("p");
invalid.innerHTML = 'Invalid HTML (dynamic)';
const valid = document.createElement("p");
valid.innerHTML = 'Valid HTML (dynamic)';
section.appendChild(valid);
section.appendChild(invalid);
const paragraphs = document.querySelectorAll("p");
for (p of paragraphs) {
console.log(p.innerHTML);
}
const links = document.querySelectorAll("a");
for (a of links) {
console.log(a.getAttribute("href"));
}
<section>
<p>Invalid HTML (static)</p>
<p>Valid HTML (static)</p>
<section>
Is & actually correct within the href text, and & technically incorrect? It seems very unlikely! I've certainly never seen HTML written that way.
There's no such thing as "technically correct", let alone today when HTML is pretty well standardised. (Well, yes, there're two competing standards bodies and specs are continuously evolving, but the basics were set up long ago.)
The & symbol starts a character entity and &b is an invalid character entity. Period.
But it works! Doesn't that mean it's technically correct?
It works because browsers are explicitly designed to deal with completely broken markup, what's known as tag soup, because it was thought that it would ease usage:
<p><strong>Hello, World!</u>
<body><br itspartytime="yeah">
<pink>It works!!!</red>
But HTML entities are just an encoding artefact. That doesn't mean that URLs are not allowed to contain literal ampersands, it just means that —when in HTML context— they need to be represented as &. It's the same as when you type a backslash in a JavaScript string to escape some quotes: the backslash does not become part of your data.
Having thought up a possible (but I thought 'unlikely') explanation - which I put in as an edit in the original question - I've realised that it is the answer:
Using & to represent & inside an href is technically incorrect, and & is technically correct
I gathered this initially from this SO answer https://stackoverflow.com/a/16168585/795690, and I think it is relevant that (as it also says in that answer) the idea that & is the correct way to represent & in an href is not as widely understood as the idea that & is the correct way to represent & in body text.
Once you do understand this, it makes sense that what the browser is doing is right, and that the innerHTML value which comes back represents the link correctly.
EDIT:
#ÁlvaroGonzález gives a much longer answer, and it took me a while to see how everything he says applies, so I thought I'd try to explain what I didn't understand starting from where I started from, in case it helps someone else!
If you start with raw HTML with <a href="http://example.com/?a=1&b=1"> and then you inspect the DOM in the browser, or look at the value of the href attribute in JS then you see "http://example.com/?a=1&b=1" everywhere. So it looks as if nothing has changed, and nothing was wrong. What I didn't understand is that actually the browser has parsed a technically incorrect href (with invalid entities) to be able to display this to you! (Yes, LOTS of people use this 'broken' format!)
To see this first hand, load this longer HTML example into your browser:
<html>
<body style="font-family: sans-serif">
<p>Now & then http://example.com/?a=1&b=2</p>
<p>Now & then http://example.com/?a=1&b=2</p>
<p>Now & then http://example.com/?a=1&b=2</p>
</body>
</html>
then in your javascript console try running this code taken from #ÁlvaroGonzález's answer:
const paragraphs = document.querySelectorAll("p");
for (p of paragraphs) {
console.log(p.innerHTML);
}
const links = document.querySelectorAll("a");
for (a of links) {
console.log(a.getAttribute("href"));
}
Also try clicking on the links to see where they go.
Once you've made sense of everything that you see there, it is no longer surprising how innerHTML works!
I am trying to write a browser test using selenium-webdriverjs. When I call the following code snippet, I get Error:Error response: 13.
browser.waitForCondition('var element = document.querySelector(".selector"); var style = document.defaultView.getComputedStyle(element,null); style =' + btnColor ,timeout);
I am waiting for a condition which I would like to get a computed css style from an element obtained from a css selector. Then the computed css style is compared to a variable called btnColor. (I know that it is also possible to do the same thing using a Webdriver JS API method called getComputedCss. However, I am interested in using waitForCondition to achieve the same purpose.)
I would like to know how to properly use waitForCondition to achieve what I want to do as said above and why the code snippet is throwing the error.
Thanks in advance!
I have found my answer to this question.I have made several javascript mistakes in the expression. The following is the code snippet I have used to solve my problem.
browser.waitForCondition('var element = window.document.querySelector(".selector"); var style = window.document.defaultView.getComputedStyle(element,null).getPropertyValue("background-color"); style ="' + btnColor + '"',timeout);
1) In order to use document, you need to call the window object first.
2) In order to get the computed background-color, I need to use the method .getPropertyValue().
3) btnColor contains a string. Therefore I need to put a double-quotation around it for the interpreter to recognize it as a string.
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"), "");
}
For example in javascript code running on the page we have something like:
var data = '<html>\n <body>\n I want this text ...\n </body>\n</html>';
I'd like to use and at least know if its possible to get the text in the body of that html string without throwing the whole html string into the DOM and selecting from there.
First, it's a string:
var arbitrary = '<html><body>\nSomething<p>This</p>...</body></html>';
Now jQuery turns it into an unattached DOM fragment, applying its internal .clean() method to strip away things like the extra <html>, <body>, etc.
var $frag = $( arbitrary );
You can manipulate this with jQuery functions, even if it's still a fragment:
alert( $frag.filter('p').get() ); // says "<p>This</p>"
Or of course just get the text content as in your question:
alert( $frag.text() ); // includes "This" in my contrived example
// along with line breaks and other text, etc
You can also later attach the fragment to the DOM:
$('div#something_real').append( $frag );
Where possible, it's often a good strategy to do complicated manipulation on fragments while they're unattached, and then slip them into the "real" page when you're done.
The correct answer to this question, in this exact phrasing, is NO.
If you write something like var a = $("<div>test</div>"), jQuery will add that div to the DOM, and then construct a jQuery object around it.
If you want to do without bothering the DOM, you will have to parse it yourself. Regular expressions are your friend.
It would be easiest, I think, to put that into the DOM and get it from there, then remove it from the DOM again.
Jquery itself is full of tricks like this. It's adding all sorts off stuff into the DOM all the time, including when you build something using $('<p>some html</p>'). So if you went down that road you'd still effectively be placing stuff into the DOM then removing it again, temporarily, except that it'd be Jquery doing it.
John Resig (jQuery author) created a pure JS HTML parser that you might find useful. An example from that page:
var dom = HTMLtoDOM("<p>Data: <input disabled>");
dom.getElementsByTagName("body").length == 1
dom.getElementsByTagName("p").length == 1
Buuuut... This question contains a constraint that I think you need to be more critical of. Rather than working around a hard-coded HTML string in a JS variable, can you not reconsider why it's that way in the first place? WHAT is that hard-coded string used for?
If it's just sitting there in the script, re-write it as a proper object.
If it's the response from an AJAX call, there is a perfectly good jQuery AJAX API already there. (Added: although jQuery just returns it as a string without any ability to parse it, so I guess you're back to square one there.)
Before throwing it in the DOM that is just a plain string.
You can sure use REGEX.