Do an action based on presence of ALT attribute with Javascript - javascript

I have some javascript which looks at the body and finds words and if one is present, it outputs a div. This is useful for many things, however...
What I need to do is also look at the body and all the ALT tags for the page as well.
I found this: Use javascript to hide element based on ALT TAG only?
Which seems to change the ALT attribute, however I want to perform an action.
Here's my JS so far.
var bodytext = $('body').text();
if(bodytext.toLowerCase().indexOf('one' || 'two')==-1)
return;
var elem = $("<div>Text Here</div>");
Thank you.
P.S. I am a N00B/ relatively new at JS, I am doing this for a small project, so I am not sure where to start for this in terms of JS functions.

Updated Answer
Try this out, I commented the code to explain it a bit.
// build array of triggers
var triggers = ['trigger1','trigger2','trigger3'];
// wait for page to load
$(function() {
// show loading overlay
$('body').append('<div id="mypluginname-overlay" style="height:100%;width:100%;background-color:#FFF;"></div>');
// check page title
var $title = $('head title');
for(trigger of triggers) {
if($($title).innerHTML.toLowerCase().indexOf(trigger) >= 0) {
$($title).innerHTML = '*censored*';
}
}
// check all meta
$('meta').each(function() {
var $meta = $(this);
for(trigger of triggers) {
if($($meta).attr('name').toLowerCase().indexOf(trigger) >= 0) {
censorPage();
return; //stop script if entire page must be censored
} else if($($meta).attr('content').toLowerCase().indexOf(trigger) >= 0) {
censorPage();
return; //stop script if entire page must be censored
}
}
});
// check all img
$('img').each(function() {
var $img = $(this);
for(trigger of triggers) {
if($($img).attr('alt').toLowerCase().indexOf(trigger) >= 0) {
censor($img);
}
}
});
// check all video
$('video').each(function() {
var $video = $(this);
for(trigger of triggers) {
if($($video).attr('alt').toLowerCase().indexOf(trigger) >= 0) {
censor($video);
}
}
});
// if you want to be extra careful and check things like background image name,
// you'll have to run this code here - very inefficent
// but necessary if you want to check every single element's background image name:
for($element of $('body').children()) {
for(trigger of triggers) {
if($($element).css('background-image').toLowerCase().indexOf(trigger) >= 0) {
$($element).css('background-image','');
}
}
}
, function() { // Not sure if this is totally correct syntax, but use a callback function to determine when
// when the rest of the script has finished running
// hide overlay
$('#mypluginname-overlay').fadeOut(500);
}});
function censor($element) {
// just a basic example, you'll probably want to make this more complex to overlay it properly
$element.innerHTML = 'new content';
}
function censorPage() {
// just a basic example, you'll probably want to make this more complex to overlay it properly
$('body').innerHTML = 'new content';
}
---Original Answer---
I'm not sure exactly what you would like to do here, you should add more detail. However if you choose to use jQuery, it provides tons of useful methods including the method .attr(), which lets you get the value of any attribute of any element.
Example:
var alt = $('#my-selector').attr('alt');
if (alt == 'whatYouWant') {
alert('yay');
} else {
alert('nay');
}

You're using jQuery lib, you could select elements by attribute like:
$('[alt="one"]').each(function(el){
// do something
var x = $(el).arrt('alt');
});
If you use selector $('[alt]') you can get elements that have this attribute set, and then check the value of the element if you have a more complicated selection.
Than you have to change your return, as you could not put a div inside an ALT tag, it didn't work.
Here is about what is your expected output.
UPDATE
As you want to change all images and video in a page, the way to do this with jquery is through $.replaceWith():
$('img,video').replaceWith($('<div>Text Here</div>'));
If you need to filter the elements:
$('img,video').each(function(el){
if($(el).prop('tagName') == 'IMG' &&
$(el).attr('alt') == 'the text...') {
$(el).replaceWith($('<div>Text Here</div>'));
}
})
But I'm not an expert on Chrome Extensions, I just put this code here in jQuery, as you was using jQuery.
Of course it could be done, with much code with plain javascript and the DOM API.

Related

How to hide an element if the page contains a specific url / word?

With JavaScript I'm trying to hide an element that contains a text message when the page URL is my-website.com/login/?lost_pass=1. I managed to hide the tag but it doesn't work as I expected.
The unwanted tag is actually hidden, but the same also happens when the page is my-website.com/login while it should only be hidden if the page is my-website.com/login/?lost_pass=1
So, for example, you are on my-website.com/login, but when you click "lost password" the page reloads to show a different form, so the URL becomes my-website.com/login/?lost_pass = 1
Can anyone help me with this? I don't understand where I'm wrong.
I tried this, but the tag is hidden on all pages
window.onload = function() {
if (window.location.href.indexOf('?lost_pass=1')) {
//Hide the element.
document.querySelectorAll('#msg_social')[0].style.display = 'none';
}
};
Then I tried that, but the tag is not hidden in any of the pages
if (window.location.href.indexOf("?lost_pass=1") != -1) {
$("#msg_social").hide();
}
Your onload code has a if that always pass :
window.onload = function() {
// this if will always pass, any number will pass that if like -1, 25 etc...
if (window.location.href.indexOf('?lost_pass=1')) {
//Hide the element.
document.querySelectorAll('#msg_social')[0].style.display = 'none';
}
};
it's better to use .contains :
window.onload = function() {
if (!window.location.href.includes('?lost_pass=1')) {
//Hide the element.
document.querySelectorAll('#msg_social')[0].style.display = 'none';
}
};
it's shorter and avoid forgetting about the != -1 thing

How to select/hide elements inside an object of type "text/html" using javascript [duplicate]

I'm using the object tag to load an html snippet within an html page.
My code looks something along these lines:
<html><object data="/html_template"></object></html>
As expected after the page is loaded some elements are added between the object tags.
I want to get those elements but I can't seem to access them.
I've tried the following
$("object").html() $("object").children() $("object")[0].innerHTML
None of these seem to work. Is there another way to get those elements?
EDIT:
A more detailed example:
consider this
<html><object data="http://www.YouTube.com/v/GGT8ZCTBoBA?fs=1&hl=en_US"></object></html>
If I try to get the html within the object I get an empty string.
http://jsfiddle.net/wwrbJ/1/
As long as you place it on the same domain you can do the following:
HTML
<html>
<object id="t" data="/html_template" type="text/html">
</object>
</html>
JavaScript
var t=document.querySelector("#t");
var htmlDocument= t.contentDocument;
Since the question is slightly unclear about whether it is also about elements, not just about the whole innerHTML: you can show element values that you know or guess with:
console.log(htmlDocument.data);
The innerHTML will provide access to the html which is in between the <object> and </object>. What is asked is how to get the html that was loaded by the object and inside the window/frame that it is producing (it has nothing to do with the code between the open and close tags).
I'm also looking for an answer to this and I'm afraid there is none. If I find one, I'll come back and post it here, but I'm looking (and not alone) for a lot of time now.
No , it's not possible to get access to a cross-origin frame !
Try this:
// wait until object loads
$('object').load(function() {
// find the element needed
page = $('object').contents().find('div');
// alert to check
alert(page.html());
});
I know this is an old question, but here goes ...
I used this on a personal website and eventually implemented it in some work projects, but this is how I hook into an svg's dom. Note that you need to run this after the object tag has loaded (so you can trigger it with an onload function). It may require adaptation for non-svg elements.
function hooksvg(elementID) { //Hook in the contentDocument of the svg so we can fire its internal scripts
var svgdoc, svgwin, returnvalue = false;
var object = (typeof elementID === 'string' ? document.getElementById(elementID) : elementID);
if (object && object.contentDocument) {
svgdoc = object.contentDocument;
}
else {
if (typeof object.getSVGDocument == _f) {
try {
svgdoc = object.getSVGDocument();
} catch (exception) {
//console.log('Neither the HTMLObjectElement nor the GetSVGDocument interface are implemented');
}
}
}
if (svgdoc && svgdoc.defaultView) {
svgwin = svgdoc.defaultView;
}
else if (object.window) {
svgwin = object.window;
}
else {
if (typeof object.getWindow == _f) {
try {
svgwin = object.getWindow();//TODO look at fixing this
}
catch (exception) {
// console.log('The DocumentView interface is not supported\r\n Non-W3C methods of obtaining "window" also failed');
}
}
}
//console.log('svgdoc is ' + svgdoc + ' and svgwin is ' + svgwin);
if (typeof svgwin === _u || typeof svgwin === null) {
returnvalue = null;
} else {
returnvalue = svgwin;
}
return returnvalue;
};
If you wanted to grab the symbol elements from the dom for the svg, your onload function could look like this:
function loadedsvg(){
var svg = hooksvg('mysvgid');
var symbols = svg.document.getElementsByTagName('symbol');
}
You could use the following code to read object data once its loaded completely and is of the same domain:
HTML-
<html>
<div class="main">
<object data="/html_template">
</object>
</div>
</html>
Jquery-
$('.main object').load(function() {
var obj = $('.main object')[0].contentDocument.children;
console.log(obj);
});
Hope this helps!
Here goes a sample piece of code which works. Not sure what the problem is with your code.
<html>
<script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js"></script>
<script type="text/javascript">
$(document).ready(function(){
var k = $("object")[0].innerHTML;
alert(k);
$("object")[0].innerHTML = "testing";
});
</script>
<object data="/html_template">hi</object>
</html>
UPDATED
I used this line of Javascript to change the value of a input filed inside an iFrame, taken from How to pick element inside iframe using document.getElementById:
document.getElementById('iframeID').contentWindow.document.getElementById('inputID').value = 'Your Value';
In your case, since you do not have a frame, and since you want to get and not set the value, log it for example with:
console.log(document.getElementById('object').value);
And if you guess or choose an element:
console.log(document.getElementById('object').data);

Ideas for a correct function on my webpage?

I am having problems with a javascript function. I want to replace an icon by changing the class.
On my page, I have the following element:
<i class="wait icon" alt="{webui_botstatenotavailable}" title="{webui_botstatenotavailable}" id="{botname}"></i>
The following javascript should change the class, but it does not work:
function incomingBotStatusList(http_request, statusOff, statusOn)
{
if (http_request.readyState == 4)
{
if (http_request.status == 200)
{
if (http_request.responseText.length < 7)
{
// Error
}
else
{
var botStatusList = JSON.parse(http_request.responseText);
for (var key in botStatusList)
{
if (botStatusList.hasOwnProperty(key))
{
var botStatusImage = document.getElementById(key);
if (botStatusImage != null)
{
if (botStatusList[key] == 0)
{
botStatusImage.class.innerHTML = "images/bullet_red.png";
botStatusImage.title = statusOff;
botStatusImage.alt = statusOff;
}
else if (botStatusList[key] == 1)
{
botStatusImage.class.innerHTML = "<i class=\"checkmark green icon\">";
botStatusImage.alt = statusOn;
botStatusImage.title = statusOn;
}
}
}
}
}
}
}
}
Did someone from you know how it will work?
Thanks for your help!
Best Regards
Pierre
I see a couple of problems with your code. First, the <i> element is used to apply italic formatting to text. It is not the HTML code for an icon or an image.
Secondly, you write botStatusImage.class.innerHTML, but the Element.class does not exist, and Element.className is a string. It does not have an innerHTML attribute. So, you could write botStatusImage.className = "new_class_name"; and this would be more correct.
You should then change the image source by calling botStatusImage.setAttribute('src', new_url), where you have set new_url to the new image location.
Check out the javascript reference for the Element class that is returned from document.getElementById: check this link
My recommendation, start simple, then make it complex.
First, try to get the icon to change without the AJAX request. Try writing a function like this:
function changeIcon( imageId, newUrl ){
var element = document.getElementById( imageId );
element.setAttribute( "src", newUrl );
}
Then test this function in the console by passing calling it with the URL's manually.
Once that works, don't change it! Next add the AJAX call, and when you have the Icon url from your server response, all you do is call the function that you already wrote and tested. That way you separate the AJAX code from the image update code and you can test them separately.
The key is smaller functions. Build the easy stuff first, and then call those easy functions from the harder functions. Once you know the easy function works well, it becomes much easier to find problems in the harder functions.

How to find when reportviewer is loaded using reportviewer api

I have created a single page for all my reports and I am loading different versions of those reports (line, pie, chart, graph, etc) with a toolbar I made. All is working well there, except on the non-table type charts (line,pie,bar,etc). When those get rendered, I found that the text in the legends and series become blurry and through some research here and other places found that they are converted to images, which are then getting resized on me though a css class that is auto generated.
Firstly, what i'm trying to do:
I want to remove this class from the image that is generated at the time it is loaded. If i turn off async rendering on my report
AsyncRendering="false"
Along with this bit of jquery (targeting the div that contains the reportviewer):
$(document).ready(function () {
$('#reportDiv img').removeAttr('class');
});
Then the result is as expected. The image is not scaled and all is well. The problem, however, is that some of these reports may be quite large, resulting in the user not having any visual feedback of whether or not something is happening. I would like to continue using async rendering, so I started to look at the reportviewer javascript api.
Sys.Application.add_load(function () {
var reportViewer = $find("ctl00_mainContentPlaceHolder_ReportViewer1");
reportViewer.add_propertyChanged(viewerPropertyChanged);
});
function viewerPropertyChanged(sender, e) {
var viewer = $find("ctl00_mainContentPlaceHolder_ReportViewer1");
if (e.get_propertyName() === "isLoading") {
var button = document.getElementById("ctl00_mainContentPlaceHolder_ctlReportParamModuleId1_btnRunReport");
button.disabled = viewer.get_isLoading();
}
else {
if ($find("ctl00_mainContentPlaceHolder_ReportViewer1").get_reportAreaContent() == Microsoft.Reporting.WebFormsClient.ReportAreaContent.ReportPage) {
alert("here");
}
}
}
The first portion (isLoading) works as expected disabling the button. However immediately upon load I get
Object doesn't support property or method 'get_reportAreaContent'
Am I missing something obvious? These are the links from msdn that I used for reference:
reportviewer isLoading
reportviewer ReportAreaContentType
Bar graphs, Line graphs, pie charts, etc. are rendered as images. The images get re-sized based on the size of the report viewer control. Instead of using AsyncRendering="false", I created this javascript workaround and it has solved my problem.
var app = Sys.Application;
app.add_init(ApplicationInit);
function ApplicationInit(sender) {
var prm = Sys.WebForms.PageRequestManager.getInstance();
if (!prm.get_isInAsyncPostBack()) {
prm.add_endRequest(EndRequest)
}
}
function EndRequest(sender, args) {
var reportViewerControlId = "ReportViewer1";
if (sender._postBackControlClientIDs[0].indexOf(reportViewerControlId) >= 0) {
var reportViewerControlContainer = "reportViewerContainer"; // Id of <DIV>
var renderedReportImage = $("#" + reportViewerControlContainer + " img");
renderedReportImage.removeAttr("style").removeAttr("class");
var styleAttr = renderedReportImage.attr("style");
var classAttr = renderedReportImage.attr("class");
if (typeof styleAttr === 'undefined') {
console.log("Successfully removed the style attribute from the rendered report image!");
}
if (typeof classAttr === 'undefined') {
console.log("Successfully removed the class attribute from the rendered report image!");
}
}
}
Basically, I am listening to the endRequest of the PageRequestManager for my ReportViewerControl's ID, then simply removing the style and class attributes from the image to display it unmodified.

Why does this "loading message" script not work in FF?(javascript)

I have this script which should show the text "Loading..." while images are loading, then change the text to "loaded" when all images are loaded. I added a button to load new images to make sure that it works for dynamically loaded images as well.
This works perfectly in Chrome but in Firefox the "Loading..." text never appears. I have no idea why this would be. The page begins loading and not all images are loaded so it should create the text "Loading.." but it doesn't. Then when all images are done loading the text "Loading" appears.
I just don't get why one message would appear and the other wouldn't. Especially because there are no qualifications that have to be met before creating the "Loading..." text, it should just fire automatically.
jsfiddle Example | Full Page Example
$(document).ready(function() {
var checkComplete = function() {
if($('img').filter(function() {return $('img').prop('complete');}).length == $('img').length) {
$('.status').text('Loaded');
} else {
$('.status').text('Loading...');
}
};
$('img').on('load',function() {
checkComplete();
});
$('#button').click(function() {
$('img.a').attr('src' , 'http://farm9.staticflickr.com/8545/8675107979_ee12611e6e_o.jpg');
$('img.b').attr( 'src' , 'http://farm9.staticflickr.com/8382/8677371836_651f586c99_o.jpg');
checkComplete();
});
checkComplete();
});
You have several issues in the code.
First off, the checkComplete() function is not written correctly. It should be this:
var checkComplete = function() {
var imgs = $('img');
if(imgs.filter(function() {return this.complete;}).length == imgs.length) {
$('.status').text('Loaded');
} else {
$('.status').text('Loading...');
}
};
The main fix here is that the filter callback needs to refer to this.complete, not to $('img').prop('complete') because you are trying to filter a single item at a time.
Second off, you are relying on both .complete and .load working correctly AFTER you've changed the .src value. This is explicitly one of the cases where they do not work properly in all browsers.
The bulletproof way to work around this is to create a new image object for the new images, set the onload handler before you set the .src value and when both onload handlers have fired, you will know that both new images are loaded and you can replace the once you have in the DOM with the new ones.
Here is a version that works in FF:
$(document).ready(function() {
$('#button').click(function() {
var imgA = new Image();
var imgB = new Image();
imgA.className = "a";
imgB.className = "b";
var loaded = 0;
imgA.onload = imgB.onload = function() {
++loaded;
if (loaded == 2) {
$("img.a").replaceWith(imgA);
$("img.b").replaceWith(imgB);
$('.status').text('Loaded');
}
}
// the part with adding now to the end of the URL here is just for testing purposes to break the cache
// remove that part for deployment
var now = new Date().getTime();
imgA.src = 'http://farm9.staticflickr.com/8545/8675107979_ee12611e6e_o.jpg?' + now;
imgB.src = 'http://farm9.staticflickr.com/8382/8677371836_651f586c99_o.jpg?' + now;
$('.status').text('Loading...');
});
});
Working demo: http://jsfiddle.net/jfriend00/yy7GX/
If you want to preserve the original objects, you can use the newly created objects only for preloading the new images and then change .src after they've been preloaded like this:
$(document).ready(function() {
$('#button').click(function() {
var imgA = new Image();
var imgB = new Image();
var loaded = 0;
imgA.onload = imgB.onload = function() {
++loaded;
if (loaded == 2) {
$("img.a")[0].src = imgA.src;
$("img.b")[0].src = imgB.src;
$('.status').text('Loaded');
}
}
// the part with adding now to the end of the URL here is just for testing purposes to break the cache
// remove that part for deployment
var now = new Date().getTime();
imgA.src = 'http://farm9.staticflickr.com/8545/8675107979_ee12611e6e_o.jpg?' + now;
imgB.src = 'http://farm9.staticflickr.com/8382/8677371836_651f586c99_o.jpg?' + now;
$('.status').text('Loading...');
});
});
Working demo of this version: http://jsfiddle.net/jfriend00/ChSQ5/
From the jQuery API .load method
Caveats of the load event when used with images
A common challenge developers attempt to solve using the `.load()` shortcut is to execute a function when an image (or collection of images) have completely loaded. There are several known caveats with this that should be noted. These are:
It doesn't work consistently nor reliably cross-browser
It doesn't fire correctly in WebKit if the image src is set to the same src as before
It doesn't correctly bubble up the DOM tree
Can cease to fire for images that already live in the browser's cache

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