How to change the href through javascript or jquery? [duplicate] - javascript

This question already has answers here:
Find element without class or id within element - jQuery
(6 answers)
Closed 1 year ago.
<div id="div-id"><ul><li><a target="_blank" href="www.google.com">google</a> </li></ul></div>
How to change the href through javascript(not through getElementById,as it is not mentioned in html) or jquery?

$("body").ready(function() {
$("ul li a").attr("href", "http://www.stackoverflow.com/")
})
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<ul> <li> <a target="_blank" href="www.google.com">google</a> </li> </ul>
This is a simple way of doing it, but right now it applies this to all Links because you have no selector(class or id)

To be more precise and make it work only for a particular anchor element
$("body").ready(function() {
$("ul >li >a:contains("google").attr("href", "http://www.stackoverflow.com/")
})

document.getElementById() is not the only way to find an element in the document. You can use fairly robust selectors with something like document.querySelector(). As an extremely simple example:
<ul>
<li>
<a target="_blank" href="www.google.com">google</a>
</li>
</ul>
<script type="text/javascript">
var element = document.querySelector('a');
element.href = 'http://example.com';
</script>
Since, in the given markup, the link being targeted is the only a element in the DOM, the simple selector 'a' will identify it. In a more complex document, you can use more complex selectors. For example:
document.querySelector('ul > li > a')
Or even:
document.querySelector('a[href="www.google.com"]')
Since you've also tagged the question with jQuery, you can use the same concept of selectors there as well. Something like:
$('a').attr('href', 'http://example.com');
or:
$('a[href="www.google.com"]').attr('href', 'http://example.com');

Related

What does this line of Jquery do?

$(this).find("a[href^='/']")
I'm particularly interested in knowing this part "a[href^='/']"
jQuery uses CSS selectors. a[^='/'] will select all <a> whose href attribute starts with / which are children of whatever the this is.
See it in action:
$("ul").each(function () {
$(this).find("a[href^='/']").addClass("selected");
});
.selected {
background-color: lime;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<ul>
<li>Will not be selected</li>
<li>Will be selected</li>
</ul>
<ul>
<li>Yep</li>
<li>Nope</li>
</ul>
jQuery documentation on starts with attribute selector: https://api.jquery.com/attribute-starts-with-selector/
More on attribute selectors: https://developer.mozilla.org/en/docs/Web/CSS/Attribute_selectors
This particular code is CSS Attribute Selector to find <a> elements with an href attribute value that starts with a /.
More here: https://api.jquery.com/attribute-starts-with-selector/
It looks for a link to the href beginning with /.

Trouble using .closest function

I'm trying to make a sidebar menu for a dashboard. I want to implement this with .closest as it will fit with my code right. Here is a simple example of what I'm trying to do: https://jsfiddle.net/eu8kjzh4/10/
Why isn't the closest span's (and the only span in this case) text being replaced with a '-'? In my code, I have
$('.' + Key).closest( '.' + Key ).css("color", "#000");
This code works just fine, but the one in the jsfiddle does not.
closest traverses up the DOM and is used for nested elements.
In your markup, your div is not a descendant of your span, not even a sibling.
You have
1. To retrieve the previous sibling (the first li after the body)
2. And find the span inside the li
$(document).ready(function() {
$(".sub").prev().find('span').text('-');
});
Also, in your fiddle, you forgot to include jQuery.
Here is a working code : https://jsfiddle.net/qwc6pepr/1/
Incorrect function: .closest( selector ) Returns: jQuery
Description: For each element in the set, get the first element that matches the selector by testing the element itself and traversing up through its ancestors in the DOM tree
What you want is the prev which finds the first sibling prior to the element
$(document).ready(function() {
$('.sub').prev('li').find('span').text('-');
});
From jQuery documentation
Given a jQuery object that represents a set of DOM elements, the .closest() method searches through these elements and their ancestors in the DOM tree and constructs a new jQuery object from the matching elements
Your span is neither a Parent Element of your div.sub in the DOM, nor matches with the $(".sub") rule.
The only way to make your jQuery code work with your HTML structure :
$("#plusMinus1").text("-");
Or modify your HTML structure to match with the .closest() method requierements
Fiddle
When you go to the parent you'll end up in the body. From there you can find the span.
$(document).ready(function() {
$(".sub").parent().find("span").text("-");
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.10.1/jquery.min.js"></script>
<body>
<li>
<a class="selected" href="#" onclick="return false;">Dashboard 1 <span id="plusMinus1">+</span></a>
</li>
<div class="sub">
<ul>
<li><a id="s1" href="">Test A</a>
</li>
<li><a id="s2" href="">Test B</a>
</li>
<li><a id="s3" href="">Test C</a>
</li>
</ul>
</div>
</body>

Javascript - having trouble selecting an id

I gave my link a an id where if I click the link, I want my javascript to adjust the background image. I made a js-fiddle of a simple version of what I want here:
https://jsfiddle.net/qp8d390b/
<body background="http://www.blueskiescareers.co.uk/wp-content/uploads/2014/05/blue-sky-clouds.jpg">
<li>
<a id = "attempt1" href="#top">SNOOPY1</a>
</li>
<li>
<a>SNOOPY2</a>
</li>
<li>
<a>SNOOPY2</a>
</li>
<div id= "#top">TOP PART </div>
</body>
$(document).ready(function() {
$("a[id='attempt1']").click(function(e) {
e.preventDefault();
alert('works');
document.body.background = "https://upload.wikimedia.org/wikipedia/commons/0/02/Fried_egg,_sunny_side_up.jpg";
});
});
I'm new to selecting with javascript. Any help would be appreciated!
try to use $("#attempt1")
use # to get any id in html
Firstly your HTML is invalid; li must be in either a ul or ol and all a elements must have either a name or href attribute.
Secondly, jQuery uses CSS rules, so to select by id is $('#attempt1').
Lastly, to change the background CSS property to an image the URL string should be wrapped in url(). Try this:
$(document).ready(function() {
$("#attempt1").click(function(e) {
e.preventDefault();
$('body').css('background', 'url("https://upload.wikimedia.org/wikipedia/commons/0/02/Fried_egg,_sunny_side_up.jpg")');
});
});
You can select it with :
$('#attempt1')
You should use id-selector in this case
https://api.jquery.com/id-selector/
$("#attempt1")
The selector you used which is attribute selector is more used in inputs than in links (a elements)
https://api.jquery.com/attribute-equals-selector/
You can find more info on jQuery selectors in
https://api.jquery.com/category/selectors/
Hope it helps

CSS built with javascript only running on first call [duplicate]

This question already has answers here:
How can I apply a jQuery function to all elements with the same ID?
(4 answers)
Closed 9 years ago.
I am using the "replace" function to remove all non-numeric values in a div.
It seems Jquery replace only affects the first element.
Here is my Jquery:
$('#comment').each(function() {
var thz = $(this);
var repl = thz.html(thz.html().replace(/\D+/g, ''));
});
HTML Code:
<a id="comment1" href="#"> c2fđf011. </a>
<a id="comment1" href="#"> c20ff113. </a>
<a id="comment1" href="#"> c201gf76341. </a>
Result:
2011 c20ff113. c201gf76341.
The result I want is:
2011 20113 20176341
You have duplicate ids, Which is invalid and also jQuery ID selector(or any other id selector like document.getElementById which internally jQuery uses because element with ids are indexed by most browsers and are meant to be unique) will return only the first one that appears in DOM. Change it to class and see it working:
$('.comment').each(function() {
var thz = $(this); var repl =
thz.html(thz.html().replace(/\D+/g, ''));
});
HTML
<a class="comment1" href="#"> c2fđf011. </a>
<a class="comment1" href="#">c20ff113. </a>
<a class="comment1" href="#"> c201gf76341. </a>
By the way had your id been like this:-
<a id="comment1" href="#"> c2fđf011. </a>
<a id="comment2" href="#">c20ff113. </a>
<a id="comment3" href="#"> c201gf76341. </a>
Starts with Attribute selector will help you (But slow you down literally, since this is an attribute selector and lose the advantage of using IDs).
$('[id^=comment]').each(function() { // While using this better give a container context $('[id^=comment]', 'container').each(function...
var thz = $(this);
var repl = thz.html(thz.html().replace(/\D+/g, ''));
});
Demo
Moral: IDs must be unique
ID in a HTML page is supposed to be unique
That is the reason it targets only the first instance of the element found.
Replace the elements with class instead
$('.comment').each(function() {
// Your code
});
$('.comment').each(function() { var thz = $(this); var repl = thz.html(thz.html().replace(/\D+/g, '')); });
replace ur element with id comment to a class comment.
If you use ID several times on elements the selector will only pick the first element with that ID.
But when you use class instead, the selector will pick all the element having that class.
If you really don't want to change the html you can use selector by attribute. But as others suggested, using class instead of id is the best option here.
$('div[id="comment"]').each(function(){})

Onmouseover change CSS class from other element

I'm trying to make an JS, but since I'm not an expert on that, maybe someone could help me. I was searching for that in Google and in Stack Overflow, but didn't find what I need. I just found onmouseover that change the class in element itself. But I want something different:
I want to make a onmouseover on a tag to change the class closed to open in other element. Example:
Link
<ul class="dropdown closed"><li>Item</li></ul>
Regards,
If you include jQuery:
Add id for your elements:
Link
<ul class="dropdown closed" id="ul1"><li>Item</li></ul>
Javascript:
$("#a1").mouseover(function(){
$("#ul1").addClass("open").removeClass("closed")
})
You can use Link
And JS:
function changeClass() {
document.getElementById("other-element").className = "open";
}
More advanced JSFiddle: http://jsfiddle.net/eRdHJ/1/
<a href="#" onmouseover=$("ul.dropdown").addClass("open").removeClass("closed")>Link</a>
<ul class="dropdown closed"><li>Item</li></ul>
Here is the jsfiddle : http://jsfiddle.net/eRdHJ/2/
This will access the first <ul> on the page. To narrow it down you need to do a getElementById first to get the elements based on tag name from that point. It will then only select the children from that tag with that certain ID-name;
<script>
function changeUl() {
// Get the first found UL, anywhere in the body
document.getElementsByTagName('ul')[0].className = 'otherName';
}
</script>
Link
With ID
<script>
function changeUl() {
var wrapper = document.getElementById('wrapper');
wrapper.getElementsByTagName('ul')[0].className = 'otherName';
}
</script>
<div id="wrapper">
Link
</div>
You might want to check if there are any found tho. [0] might trigger an undefined/error if there are no <ul> found.

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