I'm trying to set up a function on my page that will iterate through a series of news titles and will strikethrough the title if it contains a specific marker.
The titles are pulled from a WordPress post database and displayed within a <div> with ID="news". Each specific title is a link <a> with class="title".
I am first collecting all the titles into an array so I can iterate through them but for some reason, it doesn't work properly.
My code is:
<script type="text/javascript">
//first I create the array
var test_DOM = document.getElementById("news").getElementsByClassName("title");
//then I set the marker
var marker = "[X]"
//then I wirte the function to iterate through the array://
function checkX() {
for(i in test_DOM){
if (i.includes(marker)) {
i = "<del>", i, "</del>";
console.log(test_DOM[i], "changed")
}
console.log(test_DOM[i].innerHTML)
}
};
//and I call the function
checkX()
An expected result would be to see the list of news to change from
[x] News 1
[EG] News 2
to
[x] News 1 <- struck through
[EG] News 2 <- still the same
However, nothing happens. I know that getElementsByClassName gets me an array of objects and that I should use .innerHTML and some point, but using it inside the function like
function checkX() {
for(i in test_DOM){
if (i.innerHTML.includes(marker)) {
i.innerHTML = "<del>", i, "</del>";
console.log(test_DOM[i], "changed")
}
console.log(test_DOM[i].innerHTML)
}
};
gives an error of "TypeError: i.innerHTML is undefined"
I think I understand what you're trying to do and have a solution for you. There are a few things that need to be updated to get the script working as you described:
Your DOM query can be shortened using document.querySelectorAll.
When using String.includes(), it is case sensitive. This means that [x] is not equal to [X], so be sure to check the correct version for your test.
As #2pha mentioned in their comment, test_DOM will return a NodeList, which is an array-like structure, but not quite an array. To convert it to an array that can be looped over as you intend, you can use [].slice.call(test_DOM).
As #VLAZ mentioned in their comment, the comma operator will not combine strings. You should use the 'string' + 'string' syntax to combine strings.
Also as #VLAZ mentioned, the for...in loop is more intended for objects, in which it will output the keys of the object, not the values, so this isn't appropriate for your use case. You can use Array.forEach() instead.
As you alluded to, the Array.includes() check should use innerHTML for its check, and innerHTML should be used to then reset the value of the element.
I included a snippet below with some modifications.
var test_DOM = document.querySelectorAll('#news .title');
var marker = '[x]';
function checkX() {
[].slice.call(test_DOM).forEach(function(elem, i) {
if(elem.innerHTML.includes(marker)) {
elem.innerHTML = '<del>' + elem.innerHTML + '</del>';
}
});
}
checkX()
<div id="news">
<h1 class="title">[x] News 1</h1>
<h1 class="title">[EG] News 2</h1>
</div>
Follow on from my comment.
ie. "getElementsByClassName() returns a "NodeList" object, not an array as may be expected". But does have a length property.
The minimal changes to your code to get it to work.
//first I create the array
var test_DOM = document.getElementById("news").getElementsByClassName("title");
//then I set the marker
var marker = "[X]"
//console.log(test_DOM);
//then I wirte the function to iterate through the array://
function checkX() {
for(i = 0; i < test_DOM.length; i++){
if (test_DOM[i].innerHTML.includes(marker)) {
test_DOM[i].innerHTML = "<del>" + test_DOM[i].innerHTML + "</del>";
//console.log(test_DOM[i], "changed")
}
//console.log(test_DOM[i].innerHTML)
}
};
//and I call the function
checkX();
<div id="news">
<h2 class="title">title 1</h2>
<h2 class="title">[X]title 2</h2>
<h2 class="title">title 3</h2>
</div>
Related
Getting a bit stuck with this one.
I'm looping through an object (dataLayer.Tests) and I'm displaying the values of my content, in a DIV. Here's an example of how this object looks:
I'm doing this by looping through my object with forEach. (And in this example, I'm just console.logging my result result3).
The problem I'm having, is that within my forEach, I want to display create/display buttons, depending on what the number is in the totalVariants key/value.
So for example, if the totalVariants === 2, I want to create 2 buttons. If it is one, I want to create 1 button.
I know I need to for loop through this particular value, but I'm not sure how to do this, within a template literal.
Here's my code.
dataLayer.Tests.forEach((element, index, array) => {
let result3 = '';
let numberOfVariants = element.totalVariants;
if (numberOfVariants >= 1) {
for (i = 0; i < numberOfVariants; i++) {
console.log("The number is ", i + 1);
}
result3 += `
<div class="CRO-variant-result">
<p>Date Launched: ${element.date}</p>
<p>Test ID: ${element.id}</p>
<p>Test Description: ${element.name}</p>
<p>Variant Active: ${element.variant}</p>
<p>Total Variants: ${element.totalVariants}</p>
${(function () {
for (i = 0; i < element.totalVariants; i++) {
return `<button>${i}</button>`
}
})()}
</div>
`
console.log("result3", result3);
};
});
I've seen solutions which include .map and object.keys, but this doesn't seem to work/return anything. (Probably as I just need to loop through a number and not array etc.
Any ideas/pointers, would be appreciated.
Basically, I'm not sure how to loop through a number, within a template literal and return x number of elements.
Thanks,
Reena
numberOfVariants is an number, not an object, so one way you could do this is create a new incrementing array of that length (Array.from(Array(numberOfVariants).keys()) does this nicely) and then map over that array as you're doing.
${Array.from(Array(numberOfVariants).keys()).map(i => (
`<button value="${i}">${i}</button>`
)).join('')}
I'm not quite sure what you want to appear inside the button (maybe the integer of the current number as you increment)?
I have an array that contains dates. and for some reason I can't get it to show on my screen I've been debugging for a few days now and I've tracked it down to a single line, but the line has worked before and I can't figure out what the issue might be.
The array looks like this:
var selectItems =
[ "05-26-2017", "06-02-2017", "06-09-2017",
"06-16-2017", "06-23-2017", "06-30-2017", "07-07-2017", "07-14-2017",
"07-21-2017", "07-28-2017"...];
It's passed as an argument from another function, but that's how it's showing in console.log().
I might be going about this the wrong way, maybe even a lot further around then I need to but this is what I've come up with:
1. function setTHead(selectItems) {
2 var formatString;
3. for (var x = 0; x < 12; x++) {
4. formatString = selectItems[x].replace(/[^0-9/-]/g, "").toString();
5. console.log(selectItems);
6. $('#datTab').append("<div id='col" + x + "' class='column'>'" + formatString + "'</div>");
7. }
8. }
the array up top is what's showing from the console.log 5 lines down.
the sixth line is what is seeming to give me issues. Nothing is put on the page at all.
I'm getting a console error saying:
jQuery.Deferred exception: selectItems is undefined setTHead#http://localhost/mySite/script.js:136:9
startUp2#http://localhost/mySite/script.js:146:5
#http://localhost/mySite/table.php:19:9
mightThrow#http://localhost/mySite/lib/jquery.js:3586:52
resolve/</process<#http://localhost/mySite/lib/jquery.js:3654:49
setTimeout handler*resolve/<#http://localhost/mySite/lib/jquery.js:3692:37
fire#http://localhost/mySite/lib/jquery.js:3320:30
fireWith#http://localhost/mySite/lib/jquery.js:3450:29
fire#http://localhost/mySite/lib/jquery.js:3458:21
fire#http://localhost/mySite/lib/jquery.js:3320:30
fireWith#http://localhost/mySite/lib/jquery.js:3450:29
ready#http://localhost/mySite/lib/jquery.js:3923:13
completed#http://localhost/mySite/lib/jquery.js:3933:9
EventListener.handleEvent*#http://localhost/mySite/lib/jquery.js:3949:9
#http://localhost/mySite/lib/jquery.js:39:9
#http://localhost/mySite/lib/jquery.js:17:3
undefined
followed by:
TypeError: selectItems is undefined
and thats pointing to line 6.
if anyone has any advice I would be very much appreciative. Thank you in advance.
EDIT: A little more code:
function startTblView(defSel) {
if (defSel === true) {
setCookie('defSel', true, 7);
} else{
setCookie('defSel', false, 7);
}
saveSelected();
window.open('table.php', '_self');
defSel = getCookie('defSel');
if (defSel) {
selectItems = getDefDates();
}else {
selectItems = reGetSelected();
}
setTHead(selectItems);
}
defSel, is a boolean passed from my last page stating whether I'm doing a default view or a custom view, the custom view is passed from saveSelected();
saveSelected is a function for just saving the selected global value as a cookie so I can pull it out on the next page.
getDefDates pulls the default values for the array
reGetSelected, gets the selected array from the cookie.
I apologize for wonky naming conventions. I'm the only one working on this site and I'm just making sure the names don't overlap.
You can do this :
HTML code
<div id="datTab"></div>
JS code
var selectItems =
[ "05-26-2017", "06-02-2017", "06-09-2017",
"06-16-2017", "06-23-2017", "06-30-2017", "07-07-2017", "07-14-2017",
"07-21-2017", "07-28-2017"];
function setTHead(selectItems) {
var formatString;
$.each( selectItems, function( index, value ){
formatString = value.replace(/[^0-9/-]/g, "").toString();
$('#datTab').append("<div id='col" + index + "' class='column'>'" + value + "'</div>");
});
};
You can use $.each, its better than 'for' with javascript.
The .each() method is designed to make DOM looping constructs concise
and less error-prone. When called it iterates over the DOM elements
that are part of the jQuery object. Each time the callback runs, it is
passed the current loop iteration, beginning from 0. More importantly,
the callback is fired in the context of the current DOM element, so
the keyword this refers to the element.
I did a JsFiddle
Here.
I have an ng-repeat with a select in every item.
The user can select a value (trigging a function that pushes the an object into an array), but they can also change their mind, in which case the code just pushes a second object with the new value, duplicating the first one.
How could I manage to actually delete existing values, leaving only the last one on every ng-change?
Here's my HTML:
<select ng-change="insertproduct(pa.nom, basket)" ng-model="basket">
<option ng-repeat="select in numberofproducts">{{select}}</option>
</select>
And my javascript:
$scope.numberofproducts = [1,2,3,4,5,6,7,8,9,10]
$scope.singleorder = [];
$scope.insertproduct = function(nom, basket){
$scope.numero = {
'producte': nom,
'numero': basket
};
$scope.singleorder.push($scope.numero);
console.log($scope.singleorder);
}
The idea is to create a condition in which if the array contains an object with the parameter ´producte´ equal to the new one, delete the existing and push the new one.
Any tips?
First, use the findIndex method to check if an object with the same property is already in the singleorder array.
function duplicateOrder(order) {
return order.producte === nom;
}
var index = $scope.singleorder.findIndex(duplicateOrder);
Note: browser support for findIndex is limited; it is not supported in Internet Explorer.
Then remove the item with splice:
if(index > -1){
$scope.singleorder.splice(index, 1);
}
You can then push the new one in.
You should also clean up your coding style: don't mix french and english, and use either camelCase or snake_case for your functions to improve readability.
Observation :
Use AngularJS ngOptions attribute instead of ng-repeat.
You can check the index of the element in an array if that was already there you can easily remove previous one.
DEMO
var myApp = angular.module('myApp',[]);
myApp.controller('MyCtrl',function($scope) {
$scope.numberofproducts = [1,2,3,4,5,6,7,8,9,10]
$scope.newArray = [];
$scope.insertproduct = function(basket) {
var prevIndex = $scope.newArray.indexOf(basket);
if(prevIndex > -1) {
$scope.newArray.splice(prevIndex, 1);
} else {
$scope.newArray.push(basket);
}
console.log($scope.newArray);
}
});
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.23/angular.min.js"></script>
<div ng-app="myApp" ng-controller="MyCtrl">
<select ng-change="insertproduct(basket)" ng-model="basket" ng-options="select for select in numberofproducts">
</select>
</div>
Trying to do $('div').attr('data', 'ip') through a .each() just returns undefined.
Let's say I have 4 divs
<div class="box" data-ip="ipvalue">content</div>
<div class="box" data-ip="ipvalue">content</div>
<div class="box" data-ip="ipvalue">content</div>
<div class="box" data-ip="ipvalue">content</div>
and I need to iterate each one and get the data-ip value.
My code, it just returns undefined (server, serverObj, are variables).
var serversObj = $('.server');
serversObj.each(function(index, el) {
return $(this).data('ip');
});
What am I doing wrong?
You want to use map if you want to get all of the values of all of the elements
var ips = $(".box") //get all of the elements
.map(
function(){
return $(this).data("ip"); //get the value from the attribute
}
).get(); //returns an Array
Fiddle
Here is what the code should be for the markup sample you gave.
var serversObj = $('.box'),
Ipvals = [];
serversObj.each(function(index, el) {
Ipvals.push( $(this).data('ip'));
});
console.log( Ipvals);
You can also use $.map() to return the same array.
$('.box').each(function(){
console.log($(this).attr('data-ip'));
});
First off, this is totally wrong:
$('div').attr('data', 'ip')
This is setting an attribute called data to a value of "ip", it does nothing involving data attributes. Effectively, you're doing this: <div data='ip'>.
If you want to access a data attribute called data-ip, you want
$('div').data('ip')
If you want to access it for a series of elements, you can't just return it out of a .each loop. That value is discarded. You need to map your input set of elements to a set of outputs:
$('.server').map(function () { return $(this).data('ip') })
This will produce an array that has each element matched by .server's data-ip attribute.
Given an arbitrary HTML element with zero or more data-* attributes, how can one retrieve a list of key-value pairs for the data.
E.g. given this:
<div id='prod' data-id='10' data-cat='toy' data-cid='42'>blah</div>
I would like to be able to programmatically retrieve this:
{ "id":10, "cat":"toy", "cid":42 }
Using jQuery (v1.4.3), accessing the individual bits of data using $.data() is simple if the keys are known in advance, but it is not obvious how one can do so with arbitrary sets of data.
I'm looking for a 'simple' jQuery solution if one exists, but would not mind a lower level approach otherwise. I had a go at trying to to parse $('#prod').attributes but my lack of javascript-fu is letting me down.
update
customdata does what I need. However, including a jQuery plugin just for a fraction of its functionality seemed like an overkill.
Eyeballing the source helped me fix my own code (and improved my javascript-fu).
Here's the solution I came up with:
function getDataAttributes(node) {
var d = {},
re_dataAttr = /^data\-(.+)$/;
$.each(node.get(0).attributes, function(index, attr) {
if (re_dataAttr.test(attr.nodeName)) {
var key = attr.nodeName.match(re_dataAttr)[1];
d[key] = attr.nodeValue;
}
});
return d;
}
update 2
As demonstrated in the accepted answer, the solution is trivial with jQuery (>=1.4.4). $('#prod').data() would return the required data dict.
Actually, if you're working with jQuery, as of version 1.4.3 1.4.4 (because of the bug as mentioned in the comments below), data-* attributes are supported through .data():
As of jQuery 1.4.3 HTML 5 data-
attributes will be automatically
pulled in to jQuery's data object.
Note that strings are left intact
while JavaScript values are converted
to their associated value (this
includes booleans, numbers, objects,
arrays, and null). The data-
attributes are pulled in the first
time the data property is accessed and
then are no longer accessed or mutated
(all data values are then stored
internally in jQuery).
The jQuery.fn.data function will return all of the data- attribute inside an object as key-value pairs, with the key being the part of the attribute name after data- and the value being the value of that attribute after being converted following the rules stated above.
I've also created a simple demo if that doesn't convince you: http://jsfiddle.net/yijiang/WVfSg/
A pure JavaScript solution ought to be offered as well, as the solution is not difficult:
var a = [].filter.call(el.attributes, function(at) { return /^data-/.test(at.name); });
This gives an array of attribute objects, which have name and value properties:
if (a.length) {
var firstAttributeName = a[0].name;
var firstAttributeValue = a[0].value;
}
Edit: To take it a step further, you can get a dictionary by iterating the attributes and populating a data object:
var data = {};
[].forEach.call(el.attributes, function(attr) {
if (/^data-/.test(attr.name)) {
var camelCaseName = attr.name.substr(5).replace(/-(.)/g, function ($0, $1) {
return $1.toUpperCase();
});
data[camelCaseName] = attr.value;
}
});
You could then access the value of, for example, data-my-value="2" as data.myValue;
jsfiddle.net/3KFYf/33
Edit: If you wanted to set data attributes on your element programmatically from an object, you could:
Object.keys(data).forEach(function(key) {
var attrName = "data-" + key.replace(/[A-Z]/g, function($0) {
return "-" + $0.toLowerCase();
});
el.setAttribute(attrName, data[key]);
});
jsfiddle.net/3KFYf/34
EDIT: If you are using babel or TypeScript, or coding only for es6 browsers, this is a nice place to use es6 arrow functions, and shorten the code a bit:
var a = [].filter.call(el.attributes, at => /^data-/.test(at.name));
Have a look here:
If the browser also supports the HTML5 JavaScript API, you should be able to get the data with:
var attributes = element.dataset
or
var cat = element.dataset.cat
Oh, but I also read:
Unfortunately, the new dataset property has not yet been implemented in any browser, so in the meantime it’s best to use getAttribute and setAttribute as demonstrated earlier.
It is from May 2010.
If you use jQuery anyway, you might want to have a look at the customdata plugin. I have no experience with it though.
As mentioned above modern browsers have the The HTMLElement.dataset API.
That API gives you a DOMStringMap, and you can retrieve the list of data-* attributes simply doing:
var dataset = el.dataset; // as you asked in the question
you can also retrieve a array with the data- property's key names like
var data = Object.keys(el.dataset);
or map its values by
Object.keys(el.dataset).map(function(key){ return el.dataset[key];});
// or the ES6 way: Object.keys(el.dataset).map(key=>{ return el.dataset[key];});
and like this you can iterate those and use them without the need of filtering between all attributes of the element like we needed to do before.
You should be get the data through the dataset attributes
var data = element.dataset;
dataset is useful tool for get data-attribute
or convert gilly3's excellent answer to a jQuery method:
$.fn.info = function () {
var data = {};
[].forEach.call(this.get(0).attributes, function (attr) {
if (/^data-/.test(attr.name)) {
var camelCaseName = attr.name.substr(5).replace(/-(.)/g, function ($0, $1) {
return $1.toUpperCase();
});
data[camelCaseName] = attr.value;
}
});
return data;
}
Using: $('.foo').info();
You can just iterate over the data attributes like any other object to get keys and values, here's how to do it with $.each:
$.each($('#myEl').data(), function(key, value) {
console.log(key);
console.log(value);
});
I use nested each - for me this is the easiest solution (Easy to control/change "what you do with the values - in my example output data-attributes as ul-list) (Jquery Code)
var model = $(".model");
var ul = $("<ul>").appendTo("body");
$(model).each(function(index, item) {
ul.append($(document.createElement("li")).text($(this).text()));
$.each($(this).data(), function(key, value) {
ul.append($(document.createElement("strong")).text(key + ": " + value));
ul.append($(document.createElement("br")));
}); //inner each
ul.append($(document.createElement("hr")));
}); // outer each
/*print html*/
var htmlString = $("ul").html();
$("code").text(htmlString);
<script src="https://cdnjs.cloudflare.com/ajax/libs/prism/1.17.1/prism.min.js"></script>
<link href="https://cdnjs.cloudflare.com/ajax/libs/prism/1.17.1/themes/prism-okaidia.min.css" rel="stylesheet"/>
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<h1 id="demo"></h1>
<ul>
<li class="model" data-price="45$" data-location="Italy" data-id="1234">Model 1</li>
<li class="model" data-price="75$" data-location="Israel" data-id="4321">Model 2</li>
<li class="model" data-price="99$" data-location="France" data-id="1212">Model 3</li>
</ul>
<pre>
<code class="language-html">
</code>
</pre>
<h2>Generate list by code</h2>
<br>
Codepen: https://codepen.io/ezra_siton/pen/GRgRwNw?editors=1111
One way of finding all data attributes is using element.attributes. Using .attributes, you can loop through all of the element attributes, filtering out the items which include the string "data-".
let element = document.getElementById("element");
function getDataAttributes(element){
let elementAttributes = {},
i = 0;
while(i < element.attributes.length){
if(element.attributes[i].name.includes("data-")){
elementAttributes[element.attributes[i].name] = element.attributes[i].value
}
i++;
}
return elementAttributes;
}
If you know the name of keys you can also use object destructuring to get values like this
const {id, cat, cid } = document.getElementById('prod').dataset;
You can also skip keys you don't need and get the ones you need like this
const { cid, id } = document.getElementById('prod').dataset;
100% Javascript no jQuery ;)
DOMStringMap :
console.log(document.getElementById('target-element-id').dataset);
or custom variable :
var data = {};
Object.entries(document.getElementById('target-element-id').dataset).forEach(([key, val]) => {
data[key] = val;
});
console.log(data);