newbie javascript question. I made sure to research as much as I could before posting here, I've tried many solutions but could be searching for the wrong thing.
I've attached an image below of the issue I have. I'm trying to retrieve everything in the dark blue boxes, but I can't identify those input tags as there is nothing unique about them, I can however identify their parent divs by the class 'f-active'. When the divs have that class they have been selected by the user which is what I am interested in.
My attempt so far
var divArray = document.querySelectorAll('div.add-filter.f-active');
var arr = [];
for(var i=0; i < divArray.length; i++){
var childArray = divArray[i].children;
// console.log(childArray);
for(var i=0; i < childArray.length; i++){
if(childArray[i].tagName == "INPUT"){
var catNameCollection = arr.push(childArray[i].name);
// console.log(catNameCollection);
}
}
}
I tried to use a for loop to get all the parents, then use another for loop to select the children (input tags) and then grab the name attribute, however it is just outputing numbers. I did originally try to create 'divArray' as document.querySelectorAll('div.add-filter.f-active').children, but this and then grab the name attribute in the for loop, but this didn't return anything at all.
Any help anyone could offer would be greatly appreciated, I'd love to know what I'm doing wrong.
Thank you!
Your i is same for both loops. Use:
var divArray = document.querySelectorAll('div.add-filter.f-active');
var arr = [];
for(var i=0; i < divArray.length; i++){
var childArray = divArray[i].children;
// console.log(childArray);
for(var k=0; k < childArray.length; k++){
if(childArray[k].tagName == "INPUT"){
var catNameCollection = arr.push(childArray[k].name);
// console.log(catNameCollection);
}
}
}
Classic for-loops usually aren't the best tool for iterating through DOM elements - they add a lot of clutter and are error-prone, especially when you have to nest them.
In your case it'd be simpler to instead modify your query to directly grab all input elements with a div.f-active parent, then extract the names by iterating through them with a forEach. For example (using ES6 or higher):
const arr = [];
// Get list of all <input> elements that have <div> element parents with class f-active.
const nodes = document.querySelectorAll('div.add-filter.f-active > input');
// Extract name from each input element matched by your selector.
nodes.forEach(node => arr.push(node.name));
Or if you're stuck using ES5:
var arr = [];
var nodes = document.querySelectorAll('div.add-filter.f-active > input');
nodes.forEach(function(node) {
arr.push(node.name);
});
Here's a quick JSFiddle I put together to demonstrate the concept for you. (You'll need to open the console to see the result)
Hopefully that helps :)
Related
I have an XML file with many nodes that look just like this:
<map-item>
<location-name>U Lot (Pine Sreet)</location-name>
<link>https://maps.google.com?daddr=Pine+Avenue+Middletown+CT+06457</link>
<latitude>41.5501724</latitude>
<longitude>-72.6588056</longitude>
<icon-path>img/parking-icon.svg</icon-path>
</map-item>
I've successfully looped through all the of the map-item elements in the XML file like this:
markers = xml.documentElement.getElementsByTagName("map-item");
for (var i = 0; i < markers.length; i++) {
//do something here for each marker
}
But I'm having a hard time figuring out how to drill down and get at the child elements inside of each map-item element, such as location-name or icon-path. What do I need to do in order to grab the values of those child elements and do something with them?
You can use getElementsByTagName again, on each marker. If the xml is valid and conforms to some schema, you can expect that there is at least one element of the given name in your <marker>.
var markers = xml.documentElement.getElementsByTagName("map-item");
for (var i = 0; i < markers.length; i++) {
var marker = markers[i];
var locationName = marker.getElementsByTagName("location-name")[0].textContent;
var iconPath = marker.getElementsByTagName("icon-path")[0].textContent;
…
}
If you don't know how many child elements will be there in each <marker>, you'll have to switch on the .length of the selected list or loop again.
Have you tried with markers[0].childNodes?
for (var i = 0; i < markers[0].childNodes.length; i++) {
// NOTE: List is live, Adding or removing children will change the list
markers[0].childNodes[i];
}
See Mozilla Documentation
#Prasanth has been kind enough to demonstrate with a fiddle to demonstrate (I modified the output so it wouldn't be an alert).
Hi all i am trying to change the html of an object from an array of htmls. But i am having problem iterating properly. I managed to make it work once
EDIT
After a few complains about the clarity of my question I will rephrase it. I have a div panel called .trpanel and a button called #trigger2 (it is a next button). Then I have a series of divs with texts that contain translations. I want when I press the button (called next) to cycle through the translations one by one on the trpanel.
var ltranslation = [];
ltranslation[0] = $("#translation-en-1").html();
ltranslation[1] = $("#translation-ur-en").html();
ltranslation[2] = $("#translation-fr-en").html();
ltranslation[3] = $("#translation-it-en").html();
ltranslation[4] = $("#translation-sp-en").html();
ltranslation[5] = $("#translation-po-en").html();
ltranslation[6] = $("#translation-fr-en").html();
ltranslation[7] = $("#translation-de-en").html();
var l= ltranslation;
$("#trigger2").off('click').on('click',function(){
for (var i = 0; i <= ltranslation.length; i++){
if (i==7){i=0;}
$(".trpanel").html.ltranslation[i]; or ???//replace().ltranslation[]+i??? the code throws errors
}
});
I am quite new to Javascript and i am getting a bit confused with the types of objects and arrays and loops. I managed once to add the htmls but without replacing them ... so they all came one after the other. The i tried to change the code and it hasn't worked since. Any help will be greatly appreciated.
A lot of guessing, but seems like you are trying to do this :
var trans = $('[id^="translation-"]'),
idx = 0;
$("#trigger2").on('click',function(){
$(".trpanel").html( trans.eq(idx).html() );
idx = idx > 6 ? 0 : idx+1;
});
FIDDLE
I think you are trying to do this:
if (i == 7) {
i = 0; // I don't really know why you are doing this, but it will reset the loop
}
$(".trpanel").html(ltranslation[i]); //I'm passing ltranslation[i] to the html method. Instead of .html.ltranslation[i].
}
Also, without seeing any html, I'm not sure but I think you may want to iterate over .trpanel ?
Something like:
$(".trpanel").eq(i).html(ltranslation[i]);
Another thing (so you can make your code clearer I think). You can abstract the array population in a function, like this:
var ltranslation = [];
var languages = ["en-1", "ur-en", "fr-en", "it-en", "sp-en", "po-en", "fr-en", "de-en"];
$.each(languages, function(index) {
ltranslation[index] = $("#translation-" + this).html();
});
// Then you can use ltranslation
If you want to flip through several translations I would implement it that way:
var translations=["hej","hello", "hallo","hoy"];
var showTranslation=function(){
var current=0;
var len=translations.length;
return function(){
var direction=1;
if (current>=len) current=0;
$("#text").text(translations[current]);
current+=direction;
}
}();
$("#butt").on("click", showTranslation);
Fiddle: http://jsfiddle.net/Xr9fz/
Further: You should give your translations a class, so you could easily grab all of them with a single line:
$(".translation).each(function(index,value){ ltranslation.push(value); })
From the question : I managed once to add the htmls but without replacing them -
I think you want to add all of these items into $(".trpanel"). First, dont take the HTML of each element, clone the element itself :
//method ripped from Nico's answer.
var ltranslation = [];
var languages = ["en-1", "ur-en", "fr-en", "it-en", "sp-en", "po-en", "fr-en", "de-en"];
$.each(languages, function(index) {
ltranslation[index] = $("#translation-" + this).clone();
});
Then you could append everything into the container, so add the htmls but without replacing them. append takes in an array without replacing the previous html.
$("#trigger2").off('click').on('click',function() {
$(".trpanel").append(ltranslation);
});
I don't know what exactly you're tring to do, but I've put comments in your code to help you better understand what your code is doing. The net effect of your code is this (which I doubt you want) :
$("#trigger2").off('click').on('click',function(){
$(".trpanel").html(ltranslation[7]);
});
This is your code with some comments and minor changes
var ltranslation = [];
ltranslation[0] = $("#translation-en-1").html();
ltranslation[1] = $("#translation-ur-en").html();
ltranslation[2] = $("#translation-fr-en").html();
ltranslation[3] = $("#translation-it-en").html();
ltranslation[4] = $("#translation-sp-en").html();
ltranslation[5] = $("#translation-po-en").html();
ltranslation[6] = $("#translation-fr-en").html();
ltranslation[7] = $("#translation-de-en").html();
var l= ltranslation;
$("#trigger2").off('click').on('click',function(){
for (var i = 0; i < ltranslation.length; i++){
//if (i==7){i=0;} <-- This will cause an infinite loop won't it? are you trying to reset i? i will reset next time loop is called,
$(".trpanel").html(ltranslation[i]); //<-- this will overwrite elements with class .trpanel ltranslation.length times...
///you'll see only the value of translation[7] in the end
}
});
EDIT
To do what you want to do based on your comments, try this:
var ltranslation = [];
ltranslation[0] = $("#translation-en-1").html();
ltranslation[1] = $("#translation-ur-en").html();
ltranslation[2] = $("#translation-fr-en").html();
ltranslation[3] = $("#translation-it-en").html();
ltranslation[4] = $("#translation-sp-en").html();
ltranslation[5] = $("#translation-po-en").html();
ltranslation[6] = $("#translation-fr-en").html();
ltranslation[7] = $("#translation-de-en").html();
var counter = 0;//a global counter variable
$("#trigger2").click(function(){ //eeverytime button is clicked do this
$(".trpanel").html(ltranslation[counter]); //set the html to an element of array
counter++; //increment counter
if(counter==ltranslation.length) //reset the counter if its bigger than array len
counter=0;
});
The following is my JSON data in a div:
[{"Identifier":"1","Label":"10 Day","Categories":"Standard","UpdatedBy":"Lno","UpdatedAt":"01-02-2013","RefId":"0","ComType":"1","Cs":["944"],"AM":"Error Message","Message":"asdfasdf","Combiner":[{"uniqueID":"1","type":"7","rule":""}]}]
I am accessing it through a JS object:
var myArrayVar=JSON.parse(document.getElementById("populateDT").innerHTML);
I want to iterate over this JS object. The following is my code, but it doesn't access my key/value fields:
for(var i=0; i<=myArrayVar.length;i++){
for(var j=0; j<=myArrayVar.Combiner.length; j++){
var sessionUniqueId= myArrayVar.Combiner[j].uniqueID;
alert(sessionUniqueId);
var sessionType=myArrayVar.Combiner[j].type;
alert(sessionType);
var sessionRule=myArrayVar.Combiner[j].rule;
alert(sessionRule);
}
}
Can anyone suggest a solution?
for (var i = 0; i < myArrayVar.length; i++) {
for (var j = 0; j < myArrayVar[i].Combiner.length; j++) {
var sessionUniqueId = myArrayVar[i].Combiner[j].uniqueID;
alert(sessionUniqueId);
var sessionType = myArrayVar[i].Combiner[j].type;
alert(sessionType);
var sessionRule = myArrayVar[i].Combiner[j].rule;
alert(sessionRule);
}
}
You never use i. You need it to access the current array element, for example:
for(var j=0; j<=myArrayVar[i].Combiner.length; j++){
myArrayVar is your array, myArrayVar[i] is the i-th element in that array and myArrayVar[i].Combiner is the combiner (array) property of the i-th element.
You'll make it yourself a lot easier if you give the current element a name as well. (You probably want to come up with a less generic name such as current though.)
for(var i=0; i<myArrayVar.length;i++){
var current=myArrayVar[i];
for(var j=0; j<current.Combiner.length; j++){
var sessionUniqueId=current.Combiner[j].uniqueID;
alert(sessionUniqueId);
var sessionType=current.Combiner[j].type;
alert(sessionType);
var sessionRule=current.Combiner[j].rule;
alert(sessionRule);
}
}
Also, i cannot equal myArrayVar.length as that index is already out of bounds. Your loop condition should have < instead of <=.
You have an array with one element. That element is in myArrayVar[0] and it is an object. To iterate over the object use a for ... in loop.
var myObj = myArrayVar[0];
for(var key in myObj){
var value = myObj[key];
console.log(key, value);
}
You should also use console.log for debugging. It will show you more information about objects than alert can.
Try using "<" instead of "<=" in the for loops, and "myArrayVar[i].Combiner" instead of "myArrayVar.Combiner".
There are a couple of problems I see. First, your i and j variables go one spot too far. They should be using < instead of <=.
Secondly, you're declaring variables inside the loop. That's fine, but JavaScript isn't block scoped, so you really end up with the same three variables overwriting each other as many times as there are items in the list. Your example data only has one item so you probably won't notice the overwriting problem just yet–but once you have multiple items in the list it could be a problem.
I am a YUI(AUI) beginner. In jQuery I would do
$(image).find(selector).text();
How can this be achieved in YUI?
AUI().use('event', 'node', function(A) {
var subImages = A.all('.sub_image_conatiner');
for (var i = 0; i < subImages.size(); i++){
var image = subImages.get(i);
//get child elements of image here
}
});
I thought Y.all(foo).all(selector).get('text') would just work but it unfortunately doesn't.
I'd recommend that you use only one selector to match the sub elements:
Y.all('.parent-class .child-class').get('text');
If you can't, then you don't have to iterate through the nodes like a normal JS array. You can use .each().
var texts = [];
Y.all(foo).each(function (node, i) {
texts = texts.concat(node.all(bar).get('text'));
});
console.log(texts);
I'll file a bug with YUI to see if it makes sense to add Y.NodeList.prototype.all
I want to return an array when one of the elements matches an item within an array.
Is the below code the fastest way to loop through an array when a value matches in a javascript array of arrays?
Note : Welcome any suggestions to modify the variable relatedVideosArray to make it a different data structure for better performance.
var relatedVideosArray = [
["1047694110001"],
["1047694111001", "1019385098001","1020367665001","1020367662001", "1019385097001", "1020367667001"],
["1040885813001"],
["1019385094001", "1019385096001"],
["952541791001", "952544511001", "952544512001", "952544508001", "952541790001","952580933001", "952580934001", "1051906367001"]
]
function getRelatedVideos(videoClicked){
var tempStoreArray = [];
var getCurrentId = videoClicked;
var relVideoslen = relatedVideosArray.length;
for(var i in relatedVideosArray) {
tempStoreArray = relatedVideosArray[i];
for(var j in tempStoreArray){
if(tempStoreArray[j] == getCurrentId){
return relatedVideosArray[i];
}
}
}
}
Update: I initially thought of making a key of video ids and values as all the related ids, but I want to display the key as well as all the related ids if any of the ids within the value array are clicked. Hope this helps to explain the constraint I have.
Modern day browsers support Array indexOf.
For the people saying the array indexOf is slower, basic tests on speed.
var values = [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20];
console.time("for");
for(var i=0;i<1000;i++){
for(var j=0;j<=values.length;j++){
if(values[j]===20) break;
}
}
console.timeEnd("for");
console.time("reverse for");
for(i=0;i<1000;i++){
for(var j=values.length-1;j>=0;j--){
if(values[j]===1) break;
}
}
console.timeEnd("reverse for");
console.time("while");
for(i=0;i<1000;i++){
var j=0;
while (j<values.length){
if(values[j]===20) break;
j++;
}
}
console.timeEnd("while");
console.time("reverse while");
for(i=0;i<1000;i++){
var j=values.length-1;
while (j>=0){
if(values[j]===1) break;
j--;
}
}
console.timeEnd("reverse while");
console.time("indexOf");
for(var i=0;i<1000;i++){
var x = values.indexOf(20);
}
console.timeEnd("indexOf");
console.time("toString reg exp");
for(var i=0;i<1000;i++){
var x = (/(,|^)20(,|$)/).test(values.toString);
}
console.timeEnd("toString reg exp");
Two possible solutions:
var relatedVideosArray = [
["1047694110001"],
["1047694111001", "1019385098001","1020367665001","1020367662001", "1019385097001", "1020367667001"],
["1040885813001"],
["1019385094001", "1019385096001"],
["952541791001", "952544511001", "952544512001", "952544508001", "952541790001","952580933001", "952580934001", "1051906367001"]
]
//var getCurrentId = "1019385098001";
var getCurrentId = "1040885813001";
console.time("indexOf");
var tempStoreArray = [];
for(var i = relatedVideosArray.length-1; i>=0; i--){
var subArr = relatedVideosArray[i];
if(subArr.indexOf(getCurrentId)!==-1){
tempStoreArray.push(subArr);
}
}
console.timeEnd("indexOf");
console.log(tempStoreArray);
console.time("toString reg exp");
var tempStoreArray = [];
var re = new RegExp("(,|^)" + getCurrentId + "(,|$)");
for(var i = relatedVideosArray.length-1; i>=0; i--){
var subArr = relatedVideosArray[i];
if(re.test(subArr.toString())){
tempStoreArray.push(subArr);
}
}
console.timeEnd("toString reg exp");
console.log(tempStoreArray);
I believe so if you keep your current structure. Unless you have a way of 'flattening' the array first, so that rather than being nested, there is simply one array with all the values. If this is out of your control or impractical, then you have no other choice than to iterate over every element and its elements.
Otherwise, would you be able to add the values to a map? The current video id would be the key, and the value would be the list of related videos.
If you have control over the data structure then I highly recommend changing it to something more amenable to the type of searches you are performing. First thing that comes to mind is an array of associative arrays. Each of your video arrays would be keyed with the video id ( set the value to anything you want ). That would make your search O(n), where n = the total number of video lists you have.
I'll post some code for this when I get in front of the computer.