Unable to replace the class of div element - no method named css - javascript

I want to replace the old class of html element with the new one using jQuery. Here is what I'm doing:
var elem = $('.my_selector')[0];
elem.css('class', 'my_new_class');
But I get the error saying "Uncaught type error: Object#<HtmlDivElement> has no method css.
How do I fix it?

The problem is that you are trying to call jQuery method css() (even not relevant here) from DOM element, which is derived with [0]. You can use toggleClass() to do the job:
$(".my_selector:first").toggleClass("my_selector my_new_class");

$('.my_selector')[0] is returning you a DOM element, not a jQuery Object. You'll also want to use the addClass method rather than css. To get the first element, you can use the :first pseudoselector.
So this should be what you are looking for:
$('.my_selector:first').removeClass('my_selector').addClass('my_new_class');
EDIT You can use either removeClass/addClass or toggleClass. Either are fine. Explicitly adding the new class may be safer if you have a case where an element can have both classes at the same time since toggleClass will remove both classes.

var elem = $('.my_selector')[0];
This will return the DOM element, not a jQuery object. Simply change it to this...
var elem = $('.my_selector');
To get just the first element that matches the selector, use this...
var elem = $('.my_selector').first();
Also, you have...
elem.css('class', 'my_new_class');
This is incorrect and should be changed to this...
elem.attr('class', 'my_new_class');

Try this ,
var elem = $(".my_selector");
elem.class("newclass");
otherwise you can do,
var elem = $(".my_selector");
elem.removeClass("my_selector");
elem.addClass("newclass");

$(".my_selector").removeClass('currentClass').addClass('newClass');

As said, you need the jquery object of the first element. A good method could be this:
$('.my_selector').first().css('class', 'my_new_class');
Moreover the method signature is .css( propertyName, value ) so its intented to set a css property not to change a class. To do that you need to remove old class and add new one with .removeClass and .addClass respectively.

$($('.my_selector')[0]).css('class', 'my_new_class');
document.getElementsByClassName('my_selector')[0].className = 'my_new_class';

Related

jQuery - addClass not adding class to html element

I try to add CSS class to <li> element, when I click on the button but addClass not working.
Here is my JS:
$('.test').click(function(event) {
var centrum1 = $('.p17');
$('section.bok-map').find( centrum1 ).addClass('active-region');
});
And this how is looking HTML code:
Where is the problem? find() returns true.
Here is demo: http://demo.vrs-factory.pl/mapDemo/
You had a couple of errors, as you were not selecting the correct element, hence the length of the selector was 0.
Firstly, the class is called pl7 not p17 and secondly, when using removeClass you don't put the . before the name of the class. As you are using removeClass it is understood that you want to target a class, hence not requiring you to specify this by adding the dot.
<script>
var centrum1 = $('.pl7');
$('.test').click(function(event) {
$('section.bok-map').find( centrum1 ).removeClass('pl7');
});
</script>
Also, it may be worth noting that since you are only referencing$(.pl7) once you do not necessarily have to assign it to a variable. You could also write it as below. It is up to you.
$('.test').click(function(event) {
$('section.bok-map').find('.pl7').removeClass('pl7');
});

Put an id to a parent element

I wanted to put an id in my element's parent element. Below is my code:
<div>
<div id="child"></div>
<div>
Im aware that jquery has a way to select a parent element , but I dont know how what method shall I use to put an id to it. Below is my jquery code:
div_resizable = $( "#child" ).parent();
div_resizable.id = "div_resizable";
Above code doesnt work with me. It doesnt throw an error, but no changes had taken effect. Any solution to my problem?
For achieve what you want, you can use the jquery attr:
$("#child" ).parent().attr('id', 'newID');
Or you can use the prop:
$("#child" ).parent().prop('id', 'newID');
And you can check the difference between the two here: difference between prop() and attr()
Of course div_resizable.id = "div_resizable" doesn't work. div_resizeable is an jQuery array and you are trying to assign id to it.
Try .attr instead:
$("#child").parent().attr({id: "div_resizable"});
To set a property on the first element inside a jQuery result object:
div_resizable = $( "#child" ).parent()[0];
// ^^^
div_resizable.id = "div_resizable";
This picks the first Element from the result so that you can directly access the property.
Or:
$('#child').parent().prop('id', 'div_resizable');
Use the .prop() helper method to accomplish the same thing.

Remove an element from the DOM based on a variable reference to it?

I'm dynamically creating a div like this:
var gameScoreDiv= document.createElement('div');
gameScoreDiv.innerHTML= 'Score: 0';
wrapperDiv.appendChild(gameScoreDiv);
Later I need to remove this div from DOM. How can I get rid of that div?
Is it possible to simply delete the gameScoreDiv variable and have it remove also the DOM element (I have a feeling the answer is no)?
2019 update
You can remove node with ChildNode.remove() now:
gameScoreDiv.remove()
It's supported by every major browser with the not surprising exception of IE (for which you can add a tiny polyfill though, if needed).
You can do:
gameScoreDiv.parentNode.removeChild(gameScoreDiv);
or, if you still have reference to the wrapperDiv:
wrapperDiv.removeChild(gameScoreDiv);
In jQuery it would be:
$(gameScoreDiv).remove();
but this will use the parentNode way, see the source.
You're looking for the removeChild method.
In your case I see that wrapperDiv is the parent element, so simply call it on that:
wrapperDiv.removeChild(gameScoreDiv);
Alternatively, in another scope where that isn't available, use parentNode to find the parent:
gameScoreDiv.parentNode.removeChild(gameScoreDiv);
you can give your dynamically created div an id, and later you can see if any element with this id exists, delete it. i.e.
var gameScoreDiv= document.createElement('div');
gameScoreDiv.setAttribute("id","divGameScore");
gameScoreDiv.innerHTML= 'Score: 0';
wrapperDiv.appendChild(gameScoreDiv);
and later:
var gameScoreDiv= document.getElementById('divGameScore');
wrapperDiv.removeChild(gameScoreDiv);
You can try this:
gameScoreDiv.id = "someID";
//Remove the div like this:
var element = document.getElementById('someID');
element.parentNode.removeChild(element);

jquery hasClass, can it be given the beginning of class name, to get the full class name

I'm trying to do something similar to this question, but it's a bit different, so the solution there isn't working for me.
<span class="a-class another-class test-top-left"></span>
I have an element (this code shows a span but it could be div span or anything). This element has a class beginning with test- (test-top-left, test-top-right etc.) I've triggered a click event on classes starting with test- and saved the clicked object as var object = this;. Simple stuff so far.
What I'm trying to do now is get the full name of that class (test-top-left). I know it starts with test- but what's the full name. The thing is that there are other classes a-class another-class and test-top-left. Can hasClass be used to get the full name of the class? I'd prefer not to use find() or filter() just because there may be additional elements within that also have class="test-"
Edit:
The code I have now is, but it gives me ALL the classes. What I need is the single class beginning with test-.
var object = this;
$(object).attr('class');
So now I for loop through all the classes and test each one separately, which seems like a lot of unnecessary code. I'm hoping jQuery has a clever way to get the exact class that was clicked right away.
Description
You can use jQuerys Attribute Contains Selector, .attr() and .click() method.
Attribute Contains Selector - Selects elements that have the specified attribute with a value containing the a given substring.
.attr() - Get the value of an attribute for the first element in the set of matched elements.
.click() - Bind an event handler to the "click" JavaScript event, or trigger that event on an element.
Sample
html
<span class="anyclass test-hello">Hello World</span>​
jQuery
$("[class*='test']").click(function() {
var object = $(this);
alert(object.attr("class").match(/(test-.*?)(?:\s+|$)/)[1])
;});
Check out the updated jsFiddle
Update
If you dont want to use regex you can do this.
$("[class*='test']").click(function() {
var object = $(this);
alert("test-" + object.attr("class").split("test-")[1].split("-"))
;});
​
More Information
jQuery - Attribute Contains Selector
jQuery - .attr()
jQuery - .click()
jsFiddle Demonstration
This should work for you:
var object = this;
var className = object.className.match(/(test-.*?)(?:\s+|$)/)[1];
Class name is the name of the class you are looking for.
If you don't want to use split or regex, you can try having the class in a separate attribute
<span class="someclass test-something" _rel="test-something">test<span>
or
<span class="someclass" _rel="test-something">test<span>
with the script
$("[_rel*='test-']").click(....
And to retrieve the attribute, use $(this).attr("_rel")

Remove element in JavaScript

In the below code how to remove the hyperlink after getting the innerHTML:
function test(obj)
{
var a=obj.innerHTML
//remove obj element here
}
$p = $('<a id="name" onclick="var ele=test(this);">').html( "test" );
$('#questions').append( $p );
You can remove an element using the DOM method removeChild. If you start with a reference to the child [as you seem to in your test function (the obj argument)], you can remove it like this:
obj.parentNode.removeChild(obj);
(Your question is also tagged jQuery but I see someone pointed you to jQuery's remove function and you said you didn't want to use that. In any case, for completeness I've noted it here.)
You're using jQuery, so just do:
$(obj).remove()

Categories

Resources