<body>
<span someAttribute="xyz">.....</span>
...
<div>
...
<span someAttribute="abc">.....</span>
...
<div someAttribute="pqr">.....</div>
...
</div>
</body>
Here is a sample html page.. I need to select the html elements by its attributes i can get the attribute values by getAttribute() but i need to select all the elements first.
How in javascript to get elements which has the attribute name as "someAttribute". Once i get the elements i can get the attribute values and use my function.
Note: i want to do this without using jquery.
In new browsers you can do:
var el = document.querySelector('[someAttribute="someValue"]');
store each element in a array the loop throught each element, and if the element contains the attribute someAttribute do somgthing.
var arr_elms = [];
arr_elms = document.body.getElementsByTagName("*");
var elms_len = arr_elms.length;
for (var i = 0; i < elms_len; i++) {
if(arr_elms[i].getAttribute("someAttribute") != null){
alert("FOUND : " + arr_elms[i].getAttribute("someAttribute"));
}
}
You can select elements by tag name using document.body.getElementsByTagName("div") to get all the div elements inside your document. This function returns an array of elements, which you can parse and filter out elements that don't match your criteria.
You can traver all elements of DOM tree.
you can use
var all = document.getElementsByTagName('*');
but this also returns the html, head and body ...
and then do a loop over all elements and look for the attributes.
I found a snippet called getElementsByAttribute(doc, tagArray, attribute, attributeValue)
You can give a try to a working fiddle: http://jsfiddle.net/Yx7EU/
Hope this can help.
Related
I'm trying to create a new div in Javascript with two spans in it, each containing a string of text. They are then meant to be inserted before div.two in div.inner.
The div I'm trying to insert it into only has a class and I cannot target it by any ID, unfortunately.
I have also created a codepen here: https://codepen.io/lisaschumann/pen/BXqJKY
Any help is massively appreciated!
HTML
<html>
<div class="inner">
<div class="one"></div>
<div class="two"></div>
</div>
</html>
JS
window.onload=function(){
var infobox = document.createElement("div");
infobox.classList.add('infobox');
var spanOne = document.createElement("div");
var spanOneText = document.createTextNode('Important text 1');
var spanTwo = document.createElement("div");
var spanTwoText = document.createTextNode('Important text 2');
spanOne.appendChild(spanOneText);
spanTwo.appendChild(spanTwoText);
infobox.appendChild(spanOne);
infobox.appendChild(spanTwo);
var targetDiv = document.getElementsByClassName("inner");
targetDiv.insertBefore(infobox, targetDiv.childNodes[1]);
}
Errors:
Cannot read property '1' of undefined
at window.onload
The main issue is that getElementsByClassName returns a live collection of nodes rather than one node and so you would need to access the correct node in that list similar to an array: targetDiv[0], perhaps.
The easier method is to use querySelector to grab the element you want using its class, for example:
var parent = document.querySelector(".inner");
var two = document.querySelector(".two");
parent.insertBefore(infobox, two);
But! there's even a shortcut method you can use here that allows you to add an HTML string direct to the DOM which might save you a bit of time, and some code.
// Create the HTML
const html = `
<div>
<span>Text alpha</span>
<span>Text beta</span>
</div>`;
// Grab the element containing your "two" class
const two = document.querySelector('.inner .two');
// Using insertAdjacentHTML to add the HTML before the two element
two.insertAdjacentHTML('beforebegin', html);
<div class="inner">Inner
<div class="one">one</div>
<div class="two">two</div>
</div>
insertAdjacentHTML
This doesn't work because of these lines
var targetDiv = document.getElementsByClassName("inner");
targetDiv.insertBefore(infobox, targetDiv.childNodes[1]);
document.getElementsByClassName returns a NodeList. targetDiv.childNodes is undefined, because childNodes doesn't exist on a NodeList.
You need to either use a list operation like Array.prototype.forEach, change getElementsByClassName to getElementByClassName (note the s) or access the first node in the node list using the array indexer syntax.
I assume you meant to do something like this:
var targetDiv = document.getElementByClassName('inner')
targetDiv.insertBefore(infobox, targetDiv.childNodes[1])
This will insert a node in between the first and second child of the first DOM node with the class inner.
Try this out , targetDiv is an array by default due to the getElementsByClassName method , even though it has a single element.Hence you need to specify the index i.e. 0 ( as it's the first element of the array)
var targetDiv = document.getElementsByClassName("inner")[0]; targetDiv.insertBefore(infobox, targetDiv.children[1]); }
Using JQuery
$(document).ready(function(){
$(`<div>Important text 1<span></span>Important text 2<span></span></div>`).insertBefore( ".inner .two" );
)
I would encourage you to use JQuery and then shift to vanilla javascript later on. You can do simple tasks like this in just few lines of code and it is also easily debuggable because of that
Is it possible to add an HTML ID via the browser console using DOM Manipulation?
For example, suppose I am dealing with the following element:
<div class="elementClass">
I can fetch via DOM with something like:
document.getElementsByClassName("elementClass");
However, is it possible to add an attribute via this type of method? If I inspect the element with chrome I can do it manually, but I am wondering if it's possible to inject that ID via JavaScript.
Thanks!
You can do:
document.getElementsByClassName("elementClass")[0].setAttribute("id", "some ID");
Yes you can modify attributes of an object (HTMLElement) via javascript
getElementsByclassName returns an array, simply iterate through the list and set the attributes you wish.
var elements = document.getElementsByClassName("elementClass");
for(var I = 0; I < elements.length; I++)
element[I].id = "element" + I;
Then you could access any of those elements with that class via
var element = document.getElementById("element" + 0); //Gets First Element
Sure.
document.getElementsByClassName('elementClass')[0].id = 'someID';
or
document.getElementsByClassName('elementClass')[0].setAttribute('id', 'someID');
Just know that if you grab elements using getElementsByClassName then it will return an array of elements (assuming any elements with the matching class exist) so modifying the array won't give you the result you want.
setAttribute() method on the DOM element should work just fine.
HTML
<div class="elementClass">
This is the content of elementClass
</div>
<button onclick="buttonClicked()">Click to add attribute id red to elementClass</button>
Javascript
function buttonClicked(){
document.getElementsByClassName("elementClass")[0].setAttribute("id", "red");
}
CSS
#red {
background-color: red;
}
PLAYGROUND
Note that manipulating the class attribute causes the browser to reflow, therefore it is worth mentioning to use setAttribute() wisely to not cause performance issue.
I have an input button where is written within a blade foreach loop in a laravel project.
<div class="v-percentage">
<input id="copycode" type="Submit" value="Embed">
</div>
I am trying to write a script that will allow me to add a target attribute on the input so each button would be unique, and do something like this answer here. The script I wrote so far it should get the element and then within a for loop to add the target which i am not sure yet how I should do this.
var elements = document.getElementById('#copycode');
alert(elements);
for(var i = 0; i < elements.length; i++)
{
//add the target to the element
}
Also, when I alert the elements is returning null. How can i work that out?
document.getElementById('copycode')
getElementById just wants the ID, not a CSS selector.
Also, this will return one element (not a NodeList). IDs are unique throughout the page. If you want to select multiple elements, use classes and getElementsByClassName.
the Javascript function getElementById only returns one element. If you are trying to get a set of elements, try to use a class
<input class="copycode" type="submit" value="Embed" />
Then you could use a jquery selector to get the set of elements and iterate over then
$(".copycode").each(function(key, element){
element.attr("target", "foo");
});
If you don't want to use jquery, use the javascript function getElementsByClassName and a for to iterate over the set of elements
var elements = document.getElementsByClassName("copycode");
for (var i = 0; i < elements.length; i++) {
elements[i].setAttribute("target", "foo");
}
You can't have more than one ID with the same name, ID should be unique per page.
The getElementById() method accesses the first element with the specified id.
If you want get all the input element then you should try getElementsByTagName()
The getElementsByTagName() method accesses all elements with the specified tagname.
document.getElementsByTagName("input");
var elements = document.getElementsByTagName("input");
alert(elements);
for(var i = 0; i < elements.length; i++)
{
//add the target to the element
}
Hope this helps!
I need a solution to remove a div without an ID tag in JavaScript only. The div looks like this <div align="center">.
Here is the full structure.
<tr id="-1">
<td class="stxt">
<div align="center">
</div>
</td>
</tr>
You need to work out how to get a reference to it, once you've done that, you can remove it using:
div.parentNode.removeChild(div);
Of course the align attribute has been deprecated, but anyway, you can find the divs with align="center" using:
var divs = document.getElementsByTagName('div');
var div;
var i = divs.length;
while (i--) {
div = divs[i];
if (div.getAttribute('align') == 'center') {
div.parentNode.removeChild(div);
}
}
Which will remove every div in the document that has align="center".
Note that the object returned by getElementsByTagName is a NodeList. If you iterate over it from 0 and remove nodes, they are removed from the live list so you will skip the node following the one you remove and you will attempt to access no existant nodes at the end. Going over the list backwards avoids these pitfalls. An alternative is to turn the NodeList into an array, but that's somewhat inefficient.
Edit
Since you edited the question, here's an update answer.
You can get a reference to the TR using getElementById:
var root = document.getElementById('-1');
Now you can go down the DOM:
var cell = root.cells[0]; // First cell in the row
var div = cell.getElementsByTagName('div')[0]; // first div
cell.removeChild(div);
Which is specific to the structure you've posted.
If you can just remove the content, you can use:
var all = document.getElementsByTagName("div");
for(i=0; i < all.length; i++) {
all[i].innerHTML = ""
}
See http://jsfiddle.net/7KVkC/
You need some way to make this div tag unique. There is another javascipt function called getElementsByTagName that you can use to get an array of all of the div tags. You can then use the DOM to check whether that div tag has the property of align="center".
For instance in the snippet below - how do I access the h1 element knowing the ID of parent element (header-inner div)?
<div id='header-inner'>
<div class='titlewrapper'>
<h1 class='title'>
Some text I want to change
</h1>
</div>
</div>
Thanks!
function findFirstDescendant(parent, tagname)
{
parent = document.getElementById(parent);
var descendants = parent.getElementsByTagName(tagname);
if ( descendants.length )
return descendants[0];
return null;
}
var header = findFirstDescendant("header-inner", "h1");
Finds the element with the given ID, queries for descendants with a given tag name, returns the first one. You could also loop on descendants to filter by other criteria; if you start heading in that direction, i recommend you check out a pre-built library such as jQuery (will save you a good deal of time writing this stuff, it gets somewhat tricky).
If you were to use jQuery as mentioned by some posters, you can get access to the element very easily like so (though technically this would return a collection of matching elements if there were more than one H1 descendant):
var element = $('#header-inner h1');
Using a library like JQuery makes things like this trivial compared to the normal ways as mentioned in other posts. Then once you have a reference to it in a jQuery object, you have even more functions available to easily manipulate its content and appearance.
If you are sure that there is only one H1 element in your div:
var parent = document.getElementById('header-inner');
var element = parent.GetElementsByTagName('h1')[0];
Going through descendants,as Shog9 showed, is a good way too.
It's been a few years since this question was asked and answered. In modern DOM, you could use querySelector:
document.querySelector('#header-inner h1').textContent = 'Different text';
<div id='header-inner'>
<div class='titlewrapper'>
<h1 class='title'>
Some text I want to change
</h1>
</div>
</div>
The simplest way of doing it with your current markup is:
document.getElementById('header-inner').getElementsByTagName('h1')[0].innerHTML = 'new text';
This assumes your H1 tag is always the first one within the 'header-inner' element.
To get the children nodes, use obj.childNodes, that returns a collection object.
To get the first child, use list[0], that returns a node.
So the complete code should be:
var div = document.getElementById('header-inner');
var divTitleWrapper = div.childNodes[0];
var h1 = divTitleWrapper.childNodes[0];
If you want to iterate over all the children, comparing if they are of class “title”, you can iterate using a for loop and the className attribute.
The code should be:
var h1 = null;
var nodeList = divTitleWrapper.childNodes;
for (i =0;i < nodeList.length;i++){
var node = nodeList[i];
if(node.className == 'title' && node.tagName == 'H1'){
h1 = node;
}
}
Here I get the H1 elements value in a div where the H1 element which has CSS class="myheader":
var nodes = document.getElementById("mydiv")
.getElementsByTagName("H1");
for(i=0;i<nodes.length;i++)
{
if(nodes.item(i).getAttribute("class") == "myheader")
alert(nodes.item(i).innerHTML);
}
Here is the markup:
<div id="mydiv">
<h1 class="myheader">Hello</h1>
</div>
I would also recommend to use jQuery if you need a heavy parsing for your DOM.