I have a legacy html document containing h1 elements which don't have ids.
What I would like to achieve is to be able, using JavaScript, to get all h1(s) and then add to each a unique ID.
I have searched but could not find a solution that works.
Try getting all of them with document.getElementsByTagName("h1"). Loop through them, check if they have an id, and work appropriately. Try:
var h1s = document.getElementsByTagName("h1");
for (var i = 0; i < h1s.length; i++) {
var h1 = h1s[i];
if (!h1.id) {
h1.id = "h1" + i + (new Date().getTime());
}
}
DEMO: http://jsfiddle.net/kTvA2/
After running the demo, if you inspect the DOM, you'll see 3 out of the 4 h1 elements have a new, unique id. The one with the id in the first place isn't changed.
Note that this code needs to run after all elements are ready/rendered, which can be achieved by putting the code inside of a window.onload handler. The demo provided is set up to implicitly run the code then.
UPDATE:
With jQuery, you could use:
$(document).ready(function () {
$("h1:not([id])").attr("id", function (i, attr) {
return "h1" + i + (new Date().getTime());
});
});
DEMO: http://jsfiddle.net/kTvA2/7/
Use querySelectorAll() to get all of your header elements, then iterate over the result and generate yor unique id for each element.
var headerElements = document.querySelectorAll('h1');
for(h in headerElements) {
if(headerElements[h] instanceof Element) {
headerElements[h].id=uniqueIDgenerator();
}
}
Related
I'm new to JQuery and I noticed this line $('#DivID [type=checkbox]') and I was wondering if I can also find the select or option tags using the same method.
Update: I have a div that has more than more tag, I'm trying to get the DropDownList/Select that it's value's just changed.
Update2 I'm using InstaFilta a JQuery plugin that filter the content based on a customized attribute appended to my content tags. Below is a snippet for the function that do the same when working with CheckBoxes, and I'm trying to edit it to work with DropDownLists/Select controls.
var $ex10Checkboxes = $('#ex10 [type=checkbox]');
$ex10Checkboxes.on('change', function() {
var checkedCategories = [];
$ex10Checkboxes.each(function() {
if ($(this).prop('checked')) {
checkedCategories.push($(this).val());
}
});
ex10.filterCategory(checkedCategories, true);
});
You would find the option tags as follows:
$("#DivID option")
Likewise the select tags:
$("#DivID select")
You can then iterate over the returned objects to inspect the individual elements:
var foo = $("#DivID option");
var i;
for (i = 0; i < foo.length; i += 1) {
console.log(foo[i].val()); //or whatever
}
To find the selected element you could check out this question:
$("#DivID option:selected")
I would suggest checking out the JQuery page on Selectors JQuery Selectors
I've got multiple a elements, that are generated on the page view by a for loop that when they are clicked, send an ajax post to the database, to mark the item in the database by its id, that is equal to the value in the a element but my code is not working, anybody have any insight on why? Thanks.
<a href='#' value='(loaded from database)' id='markAsRead'>
var element = document.getElementById('markAsRead');
element.addEventListener('click', function() {
alert(this.value);
});
Anchors don't have values like inputs do, you should use a data-attribute
<a href='#' data-value='(loaded from database)' id='markAsRead'>
var element = document.getElementById('markAsRead');
element.addEventListener('click', function() {
alert(this.getAttribute("data-value"));
});
the id attribute must be unique.
if you want to have a group of controls with the same identifier you can use the name attribite.
if you look at the functions for dom manipulation:
document.getElementById() - Element (singular)
document.getElementsByName() - Elements (plural)
An example of adding a unique (depending on circumstances) id
for (var index = 0; index < 10; index++) {
var element = document.createElement("a");
element.setAttribute("data-value", "your value");
element.setAttribute("id", "markAsRead_" + index);
element.addEventListener('click', function() {
alert(this.getAttribute("data-value"));
});
document.getElementsByTagName("body")[0].appendChild(element);
}
I want to know if we can change tag name in a tag rather than its content. i have this content
< wns id="93" onclick="wish(id)">...< /wns>
in wish function i want to change it to
< lmn id="93" onclick="wish(id)">...< /lmn>
i tried this way
document.getElementById("99").innerHTML =document.getElementById("99").replace(/wns/g,"lmn")
but it doesnot work.
plz note that i just want to alter that specific tag with specific id rather than every wns tag..
Thank you.
You can't change the tag name of an existing DOM element; instead, you have to create a replacement and then insert it where the element was.
The basics of this are to move the child nodes into the replacement and similarly to copy the attributes. So for instance:
var wns = document.getElementById("93");
var lmn = document.createElement("lmn");
var index;
// Copy the children
while (wns.firstChild) {
lmn.appendChild(wns.firstChild); // *Moves* the child
}
// Copy the attributes
for (index = wns.attributes.length - 1; index >= 0; --index) {
lmn.attributes.setNamedItem(wns.attributes[index].cloneNode());
}
// Replace it
wns.parentNode.replaceChild(lmn, wns);
Live Example: (I used div and p rather than wns and lmn, and styled them via a stylesheet with borders so you can see the change)
document.getElementById("theSpan").addEventListener("click", function() {
alert("Span clicked");
}, false);
document.getElementById("theButton").addEventListener("click", function() {
var wns = document.getElementById("target");
var lmn = document.createElement("p");
var index;
// Copy the children
while (wns.firstChild) {
lmn.appendChild(wns.firstChild); // *Moves* the child
}
// Copy the attributes
for (index = wns.attributes.length - 1; index >= 0; --index) {
lmn.attributes.setNamedItem(wns.attributes[index].cloneNode());
}
// Insert it
wns.parentNode.replaceChild(lmn, wns);
}, false);
div {
border: 1px solid green;
}
p {
border: 1px solid blue;
}
<div id="target" foo="bar" onclick="alert('hi there')">
Content before
<span id="theSpan">span in the middle</span>
Content after
</div>
<input type="button" id="theButton" value="Click Me">
See this gist for a reusable function.
Side note: I would avoid using id values that are all digits. Although they're valid in HTML (as of HTML5), they're invalid in CSS and thus you can't style those elements, or use libraries like jQuery that use CSS selectors to interact with them.
var element = document.getElementById("93");
element.outerHTML = element.outerHTML.replace(/wns/g,"lmn");
FIDDLE
There are several problems with your code:
HTML element IDs must start with an alphabetic character.
document.getElementById("99").replace(/wns/g,"lmn") is effectively running a replace command on an element. Replace is a string method so this causes an error.
You're trying to assign this result to document.getElementById("99").innerHTML, which is the HTML inside the element (the tags, attributes and all are part of the outerHTML).
You can't change an element's tagname dynamically, since it fundamentally changes it's nature. Imagine changing a textarea to a select… There are so many attributes that are exclusive to one, illegal in the other: the system cannot work!
What you can do though, is create a new element, and give it all the properties of the old element, then replace it:
<wns id="e93" onclick="wish(id)">
...
</wns>
Using the following script:
// Grab the original element
var original = document.getElementById('e93');
// Create a replacement tag of the desired type
var replacement = document.createElement('lmn');
// Grab all of the original's attributes, and pass them to the replacement
for(var i = 0, l = original.attributes.length; i < l; ++i){
var nodeName = original.attributes.item(i).nodeName;
var nodeValue = original.attributes.item(i).nodeValue;
replacement.setAttribute(nodeName, nodeValue);
}
// Persist contents
replacement.innerHTML = original.innerHTML;
// Switch!
original.parentNode.replaceChild(replacement, original);
Demo here: http://jsfiddle.net/barney/kDjuf/
You can replace the whole tag using jQuery
var element = $('#99');
element.replaceWith($(`<lmn id="${element.attr('id')}">${element.html()}</lmn>`));
[...document.querySelectorAll('.example')].forEach(div => {
div.outerHTML =
div.outerHTML
.replace(/<div/g, '<span')
.replace(/<\/div>/g, '</span>')
})
<div class="example">Hello,</div>
<div class="example">world!</div>
You can achieve this by using JavaScript or jQuery.
We can delete the DOM Element(tag in this case) and recreate using .html or .append menthods in jQuery.
$("#div-name").html("<mytag>Content here</mytag>");
OR
$("<mytag>Content here</mytag>").appendTo("#div-name");
I am looking to move or copy the contents of an HTML element. This has been asked before and I can get innerHTML() or Jquery's html() method to work, but I am trying to automate it.
If an element's ID begins with 'rep_', replace the contents of the element after the underscore.
So,
<div id="rep_target">
Hello World.
</div>
would replace:
<div id="target">
Hrm it doesn't seem to work..
</div>
I've tried:
$(document).ready(function() {
$('[id^="rep_"]').html(function() {
$(this).replaceAll($(this).replace('rep_', ''));
});
});
-and-
$(document).ready(function() {
$('[id^="rep_"]').each(function() {
$(this).replace('rep_', '').html($(this));
});
});
Neither seem to work, however, this does work, only manual:
var target = document.getElementById('rep_target').innerHTML;
document.getElementById('target').innerHTML = target;
Related, but this is only text.
JQuery replace all text for element containing string in id
You have two basic options for the first part: replace with an HTML string, or replace with actual elements.
Option #1: HTML
$('#target').html($('#rep_target').html());
Option #2: Elements
$('#target').empty().append($('#rep_target').children());
If you have no preference, the latter option is better, as the browser won't have to re-construct all the DOM bits (whenever the browser turns HTML in to elements, it takes work and thus affects performance; option #2 avoids that work by not making the browser create any new elements).
That should cover replacing the insides. You also want to change the ID of the element, and that has only one way (that I know)
var $this = $(this)
$this.attr($this.attr('id').replace('rep_', ''));
So, putting it all together, something like:
$('[id^="rep_"]').each(function() {
var $this = $(this)
// Get the ID without the "rep_" part
var nonRepId = $this.attr('id').replace('rep_', '');
// Clear the nonRep element, then add all of the rep element's children to it
$('#' + nonRepId).empty().append($this.children());
// Alternatively you could also do:
// $('#' + nonRepId).html($this.html());
// Change the ID
$this.attr(nonRepId);
// If you're done with with the repId element, you may want to delete it:
// $this.remove();
});
should do the trick. Hope that helps.
Get the id using the attr method, remove the prefix, create a selector from it, get the HTML code from the element, and return it from the function:
$('[id^="rep_"]').html(function() {
var id = $(this).attr('id');
id = id.replace('rep_', '');
var selector = '#' + id;
return $(selector).html();
});
Or simply:
$('[id^="rep_"]').html(function() {
return $('#' + $(this).attr('id').replace('rep_', '')).html();
});
From my question, my understanding is that you want to replace the id by removing the re-_ prefix and then change the content of that div. This script will do that.
$(document).ready(function() {
var items= $('[id^="rep_"]');
$.each(items,function(){
var item=$(this);
var currentid=item.attr("id");
var newId= currentid.substring(4,currentid.length);
item.attr("id",newId).html("This does not work");
alert("newid : "+newId);
});
});
Working Sample : http://jsfiddle.net/eh3RL/13/
how do i call a function to count the number of divs with an id of 'd1' after the page loads. right now i have it in my section but doesnt that execute the script before anything in the loads? because it works if i put the code below the div tags...
Firstly there should be at most one because IDs aren't meant to be repeated.
Second, in straight Javascript you can call getElementById() to verify it exists or getElementsByTagName() to loop through all the divs and count the number that match your criteria.
var elem = document.getElementById("d1");
if (elem) {
// it exists
}
or
var divs = document.getElementsByTagName("div");
var count = 0;
for (var i = 0; i < divs.length; i++) {
var div = divs[i];
if (div.id == "d1") {
count++;
}
}
But I can't guarantee the correct behaviour of this because like I said, IDs are meant to be unique and when they're not behaviour is undefined.
Use jQuery's document.ready() or hook up to the onLoad event.
well an ID should be unique so the answer should be one.
you can use <body onload='myFunc()'> to call a script once the DOM is loaded.
You need to have the function tied to the onload event, like so:
window.onload = function() {
var divElements = document.getElementById("d1");
var divCount = divElements.length;
alert(divCount);
};
For the record, you should only have one div with that ID, as having more than one is invalid and may cause problems.