I am trying to delete the child element in the dom from its parent using jquery.
Here is the code snippet.
$('#delete').live('click' , function() {
var strchild = m.split("/",2)[1];
var c = group.children(strchild);
c.remove();
});
strchild contains the id of the child element. group is the parent object. I am getting the right child element in the variable c. But the remove function fails.
Can some help me out here.
Thanks.
If you have
strchild
as the id of the element you want to remove, you can do
$("#" + strchild).remove()
assuming it is the only element with that id (it should be, that's the whole point of id).
EDIT:
With multiple ids, you would need to reference the parent specifically. This is very simple, since you say in your question that group is the parent object. This answer assumes it is the object itself, rather than the id, as your code sample implies.
$("#" + strchild, group).remove()
Adding the second argument here constrains the selector to the specifications of that second argument. So this will search the parent (group) for an element with the id strchild, and then remove that element.
Related
Suppose that I want to add a newly created paragraph (using document.createElement("p")) into an existing div (with class name "container") in one of my html files. Is there a way to do this by calling some methods?
Since there's a getElementById() method, I figured I would use a getElementByClassName() method too, but that doesn't exist; what exists is getElementsByClassName() instead. One way I can get around this is to just change my div to have an id rather than a class name, and use the getElementById() to add the paragraph into the div, but I wanted to know if there was some method that I could call that would help me retrieve a class element (rather than the elements within the class itself).
I've tried looking for this online, but what I've found are answers to "how to add class names to elements" instead, which is not what I want to know.
For one element, this will chose first in DOM order:
var p = document.createElement("p");
p.innerHTML = "p element";
document.querySelector(".container").appendChild(p);
<div class="container">container</div>
For all elements with chosen class:
[...document.querySelectorAll('.container')].forEach(el => {
var p = document.createElement("p");
p.innerHTML = "p element";
el.appendChild(p);
})
<div class="container">container</div>
<div class="container">container2</div>
HTML DOM elements' IDs have to be unique within a document - and so asking for an element by Id will return you just one element (or null if there isn't a matching element).
However a class name can be applied to multiple elements, so you would expect to get zero one or more elements when searching by class, hence the getElementsByClassName returns a collection.
So if you have a list of elements with the class name container, and you know your document (hopefully) only contains one element with that name, you can pick the first element returned by the getElementsByClassName - e.g. getElementsByClassName('container')[0]
Note - getElementsByClassName returns all elements to which the class has been directly applied, for the children of the element on which it is being called. I've interpreted your query as relating to the whole document in the context of your original question.
I have an interface that switches between displaying different div elements. When it switches which element it displays, I need to access a specific child node of that div element, with each div element having their children arranged differently.
The childNodes and children property both return an object that can only select children with item(index) which is annoying to use as the relevant child element's index is different in each div. For Protractor, I used the webmanager.by(selector) which was able to search with other parameters than index. Is there something similar I can use to select the child node with data-relevant="true". I am also unsure if that attribute is the best way to specify in the HTML which child node is relevant.
This is an Angular application if that helps.
If you want to select the child node with data-relevant="true" from some parent element, you could use the selector method
element.querySelector()
That would return the first matching element...
in your specific case it could be something like
parent-element.querySelector( "[data-relevant='true']" );
or if you want to select all paragraphs p with the data-relevant attribute value true within the parent div: parentDiv.querySelectorAll( "p[data-relevant='true']" );
You can find some examples on
http://www.w3.org/TR/selectors-api/#processing-selectors
An alternative would be to use a special class to identify which child node is relevant...
you could get this element/or many elements with getElementsByClassName(someClassName)
Code Sample With .querySelectorAll() method:
<script type="text/javascript">
window.addEventListener("load", init, false);
function init(){
var parentDiv = document.getElementById("divWithChildren");
var relevantChildren = parentDiv.querySelectorAll( "[data-relevant='true']" );
alert (relevantChildren[2].id); // this will give the id of the 3rd child element with data-relevant='true'
}
</script>
How would I go about adding multiple child elements to a parent?
This is what I would like to achieve :
<div id = "myDiv">
<div id = "child1"></div>
<div id = "child2"></div>
</div>
This would, however, make child2 a child of child1:
$("#myDiv").append("div").attr("id", "child1").append("div").attr("id","child2")
Is there any way of adding two children with different attributes using dot notation?
EDIT: How about also appending a child to child1?
$("#myDiv").append("<div id='child1'>").append("<div id='child2'>")
And another
$('#myDiv').append($('<div>', { id: 'child1' })).append($('<div>', { id: 'child2' }))
$("#myDiv").append("div").attr("id", "child1").append("div").attr("id","child2");
Appends "div" text to myDiv, then changes the id attribute of the div formerly known as "myDiv" to "child1" then appends more text and changes the id again.
Change form of your statements:
$("<div>").attr("id", "child3").add($("<div>").attr("id", "child4")).appendTo("#myDiv");
With this, jQuery creates a properly formed div, assigns and id attribute to it, then adds another div with and id. Note that the second addition with .add() is properly formed due to the $ inside there and the id attribute added before it gets added to the first one, then they both get appended.
NOTE: you can also use the pattern above or do simple string for the child of child1 as:
$("<div id='child1A'/><div id='child1B'/>").appendTo("#child1");
Worth noting this only hits the DOM once which is desired and you can build up the string to append more as well - still only hitting the DOM once with that append.
You could clone() #myDiv to a variable, loop up to the number of child elements needed, change the attribute and then appendTo #myDiv. I know right, kinda complex.
Perhaps you're better off using append two times. (In two separate lines, no chaining)
Oh wait, you could use add (Here's a fiddle : http://jsfiddle.net/w4qnk/)
$elemts = $()
$elemts = $elemts.add($('<div/>', { 'id': 'child1'}))
$elemts = $elemts.add($('<div/>', { 'id': 'child2'}))
$("#myDiv").append($elemts)
$('#cont > fieldset').each(
function(index){
var $self = $(this);
// Here how to get child elements? How to write this selector?
//$('$self > div') ?? this seems does not work.
});
$self.find("div"); // return all descendant divs
or:
$self.children("div"); // return immediate child divs
depending on whether you want immediate children or any descendants.
You can even do this to get immediate child divs, but children is prettier :
$self.find(">div");
Look at the .children method in jQuery. This will get direct children of the element, e.g.:
$self.children('div') // returns divs that are direct children
You can also use the similar .find method if you need to go deeper than one level.
$self.find('div') // returns divs that are direct children, or children of children
Also, you can select using $self as the context, like:
$('div', $self) //returns all divs within $self
using children
$(this).children('div')
or
using find
$(this).find('div');
look on this post
You can use the children() method, to get all immediate children of self.
var children = $self.children();
<div onclick="test(this)">
Test
<div id="child">child</div>
</div>
I want to change the style of the child div when the parent div is clicked. How do I reference it? I would like to be able to reference it by ID as the the html in the parent div could change and the child won't be the first child etc.
function test(el){
el.childNode["child"].style.display = "none";
}
Something like that, where I can reference the child node by id and set the style of it.
Thanks.
EDIT: Point taken with IDs needing to be unique. So let me revise my question a little. I would hate to have to create unique IDs for every element that gets added to the page. The parent div is added dynamically. (sort of like a page notes system). And then there is this child div. I would like to be able to do something like this: el.getElementsByName("options").item(0).style.display = "block";
If I replace el with document, it works fine, but it doesn't to every "options" child div on the page. Whereas, I want to be able to click the parent div, and have the child div do something (like go away for example).
If I have to dynamically create a million (exaggerated) div IDs, I will, but I would rather not. Any ideas?
In modern browsers (IE8, Firefox, Chrome, Opera, Safari) you can use querySelector():
function test(el){
el.querySelector("#child").style.display = "none";
}
For older browsers (<=IE7), you would have to use some sort of library, such as Sizzle or a framework, such as jQuery, to work with selectors.
As mentioned, IDs are supposed to be unique within a document, so it's easiest to just use document.getElementById("child").
This works well:
function test(el){
el.childNodes.item("child").style.display = "none";
}
If the argument of item() function is an integer, the function will treat it as an index. If the argument is a string, then the function searches for name or ID of element.
If the child is always going to be a specific tag then you could do it like this
function test(el)
{
var children = el.getElementsByTagName('div');// any tag could be used here..
for(var i = 0; i< children.length;i++)
{
if (children[i].getAttribute('id') == 'child') // any attribute could be used here
{
// do what ever you want with the element..
// children[i] holds the element at the moment..
}
}
}
document.getElementById('child') should return you the correct element - remember that id's need to be unique across a document to make it valid anyway.
edit : see this page - ids MUST be unique.
edit edit : alternate way to solve the problem :
<div onclick="test('child1')">
Test
<div id="child1">child</div>
</div>
then you just need the test() function to look up the element by id that you passed in.
If you want to find specific child DOM element use method querySelectorAll
var $form = document.getElementById("contactFrm");
in $form variable we can search which child element we want :)
For more details about how to use querySelectorAll check this page