Develop Reference

JavaScript array has elements but length is zero

I've done some searching around the web and nothing seems to solve my problem. I have the following jQuery code:
function youtube_data_parser(data) {
//---> parse video data - start
var qsToJson = function(qs) {
var res = {};
var pars = qs.split('&');
var kv, k, v;
for (i in pars) {
kv = pars[i].split('=');
k = kv[0];
v = kv[1];
res[k] = decodeURIComponent(v);
}
return res;
}
//---> parse video data - end
var get_video_info = qsToJson(data);
if (get_video_info.status == 'fail') {
return {
status: "error",
code: "invalid_url",
msg: "check your url or video id"
};
} else {
// remapping urls into an array of objects
//--->parse > url_encoded_fmt_stream_map > start
//will get the video urls
var tmp = get_video_info["url_encoded_fmt_stream_map"];
if (tmp) {
tmp = tmp.split(',');
for (i in tmp) {
tmp[i] = qsToJson(tmp[i]);
}
get_video_info["url_encoded_fmt_stream_map"] = tmp;
}
//--->parse > url_encoded_fmt_stream_map > end
//--->parse > player_response > start
var tmp1 = get_video_info["player_response"];
if (tmp1) {
get_video_info["player_response"] = JSON.parse(tmp1);
}
//--->parse > player_response > end
//--->parse > keywords > start
var keywords = get_video_info["keywords"];
if (keywords) {
key_words = keywords.replace(/\+/g, ' ').split(',');
for (i in key_words) {
keywords[i] = qsToJson(key_words[i]);
}
get_video_info["keywords"] = {
all: keywords.replace(/\+/g, ' '),
arr: key_words
};
}
//--->parse > keywords > end
//return data
return {
status: 'success',
raw_data: qsToJson(data),
video_info: get_video_info
};
}
}
function getVideoInfo() {
var get_video_url = $('#ytdlUrl').val();
var get_video_id = getUrlVars(get_video_url)['v'];
var video_arr_final = [];
var ajax_url = "video_info.php?id=" + get_video_id;
$.get(ajax_url, function(d1) {
var data = youtube_data_parser(d1);
var video_data = data.video_info;
var player_info = data.video_info.player_response;
var video_title = player_info.videoDetails.title.replace(/\+/g, ' ');
var fmt_list = video_data.fmt_list.split(',');
var video_thumbnail_url = video_data.thumbnail_url;
var video_arr = video_data.url_encoded_fmt_stream_map;
//create video file array
$.each(video_arr, function(i1, v1) {
var valueToPush = {};
valueToPush.video_url = v1.url;
valueToPush.video_thumbnail_url = video_thumbnail_url;
valueToPush.video_title = video_title;
$.each(fmt_list, function(i2, v2) {
var fmt = v2.split('/');
var fmt_id = fmt[0];
var fmt_quality = fmt[1];
if (fmt_id == v1.itag) {
valueToPush.fmt_id = fmt_id;
valueToPush.fmt_quality = fmt_quality;
}
});
video_arr_final.push(valueToPush);
});
});
return video_arr_final;
}
function getUrlVars(url) {
var vars = {};
var parts = url.replace(/[?&]+([^=&]+)=([^&]*)/gi, function(m, key, value) {
vars[key] = value;
});
return vars;
}
function fillInOptions(ytOptions) {
//console.log(ytOptions);
//alert(ytOptions[0]);
var ytFill = ytOptions;
console.log(ytFill);
//ytFill.forEach(function(i,v) {
var ytdlOptions = $('#ytdlOptions');
ytFill.forEach(function(i,v) {
console.log(i);
ytdlOptions.append(new Option(v.fmt_quality, v.fmt_id));
});
return true;
}
function showYTDLLoader() {
$('#ytdlInput').fadeOut(1000, function() {
$('#ytdlLoader').fadeIn(500);
});
var options = getVideoInfo();
//console.log(options);
if (fillInOptions(options) == true) {
//do rest
}
}
function showYTDLOptions() {
return true;
}
function startDownload() {
showYTDLLoader();
}
function hideYTDLLoader() {
$('#ytdlLoader').fadeOut(500);
}
function animateCSS(element, animationName, callback) {
const node = $(element);
node.addClass(animationName);
function handleAnimationEnd() {
node.removeClass(animationName);
node.animationend = null;
if (typeof callback === 'function') callback();
}
node.animationend = handleAnimationEnd();
}
When my button is clicked, I call showYTDLLoader() which gets an array of objects from the YouTube API that looks like this:
[
{
"video_url": "https://r7---sn-uxanug5-cox6.googlevideo.com/videoplayback?expire=1572496003&ei=Iw66Xa24H8PL3LUPiN25mAs&ip=2001%3A8003%3A749b%3Aa01%3A5cd8%3Ac610%3A6402%3Ad0fe&id=o-ADsVnoOoBQ6-SWzYZU7gHES06s7xQptJG6hn9WcakITY&itag=22&source=youtube&requiressl=yes&mm=31%2C29&mn=sn-uxanug5-cox6%2Csn-ntqe6n7r&ms=au%2Crdu&mv=m&mvi=6&pl=39&initcwndbps=1655000&mime=video%2Fmp4&ratebypass=yes&dur=917.768&lmt=1572418007364260&mt=1572474311&fvip=4&fexp=23842630&c=WEB&txp=5535432&sparams=expire%2Cei%2Cip%2Cid%2Citag%2Csource%2Crequiressl%2Cmime%2Cratebypass%2Cdur%2Clmt&sig=ALgxI2wwRgIhAIp-4gyUTLoXFetbY0ha_YnR7DJqsp_MNjjIxqDdfPZJAiEA_WPd21jgX9broBcigf8rcSEVoJb2_NX7t3XZQqytsSM%3D&lsparams=mm%2Cmn%2Cms%2Cmv%2Cmvi%2Cpl%2Cinitcwndbps&lsig=AHylml4wRAIgacvP3zjEq-rVEZFrX7a_hC6TR-Zab7Ii-Fbaupjs_PcCIHdZht4l4ioYL3ERz7WNiSbnOnhm5iYxEECaQXPP2hUp",
"video_title": "Arnold Schwarzenegger on Son-in-law Chris Pratt, Pranking Sylvester Stallone & Terminator’s Return",
"fmt_id": "22",
"fmt_quality": "1280x720"
},
{
"video_url": "https://r7---sn-uxanug5-cox6.googlevideo.com/videoplayback?expire=1572496003&ei=Iw66Xa24H8PL3LUPiN25mAs&ip=2001%3A8003%3A749b%3Aa01%3A5cd8%3Ac610%3A6402%3Ad0fe&id=o-ADsVnoOoBQ6-SWzYZU7gHES06s7xQptJG6hn9WcakITY&itag=18&source=youtube&requiressl=yes&mm=31%2C29&mn=sn-uxanug5-cox6%2Csn-ntqe6n7r&ms=au%2Crdu&mv=m&mvi=6&pl=39&initcwndbps=1655000&mime=video%2Fmp4&gir=yes&clen=44248820&ratebypass=yes&dur=917.768&lmt=1572416976690256&mt=1572474311&fvip=4&fexp=23842630&c=WEB&txp=5531432&sparams=expire%2Cei%2Cip%2Cid%2Citag%2Csource%2Crequiressl%2Cmime%2Cgir%2Cclen%2Cratebypass%2Cdur%2Clmt&sig=ALgxI2wwRQIhANTZJlBHFWQWCnfK11yvLiPUV26c6NzvqIMKjDwmsByMAiBUSy0ZJMo4GdHSiRU4xBDDLxLtzwKZAqAKCiB-1aViDQ%3D%3D&lsparams=mm%2Cmn%2Cms%2Cmv%2Cmvi%2Cpl%2Cinitcwndbps&lsig=AHylml4wRAIgacvP3zjEq-rVEZFrX7a_hC6TR-Zab7Ii-Fbaupjs_PcCIHdZht4l4ioYL3ERz7WNiSbnOnhm5iYxEECaQXPP2hUp",
"video_title": "Arnold Schwarzenegger on Son-in-law Chris Pratt, Pranking Sylvester Stallone & Terminator’s Return",
"fmt_id": "18",
"fmt_quality": "640x360"
}
]
But when I try and loop through each entry with fillInOptions(), my loop is never completed because the length is apparently zero. However, when I dump the array using console.log() it tells me the length is 2, and displays the above. I need to be able to add each option to my dropdown.
Thankyou!
UPDATE: Added full code, sorry!

It looks like your .forEach() is the root of the problem. The parameters of a forEach are currentValue, index like this: array.forEach(function(currentValue, index) {}); but it looks like you're using them in the opposite way
Try rewriting that iteration to this:
ytFill.forEach(function(v, i) {
console.log(i);
ytdlOptions.append(new Option(v.fmt_quality, v.fmt_id));
});
Notice the difference in the order of v and i in the parameters.

how can i return the count from a function

hi iam new to javascript, i am trying to return a count from the function my code is like below
my code
function moredbCount(contentMoreArray2, ArrHeading) {
var sampleArr = [];
for (var a = 0; a < contentMoreArray2.length; a++) {
if (ArrHeading !== 'More') {
var fullHeading = ArrHeading + '-' + contentMoreArray2[a].name;
} else {
fullHeading = contentMoreArray2[a].name;
}
sampleArr.push(fullHeading);
}
var sampleCount = sampleHeadingCount(sampleArr);
return sampleCount.then(function (resultantCount) {
return resultantCount; //Here iam getting some count like 10 and returning it to the function;
});
}
var contentCount;
var totalCount = moredbCount(contentMoreArray2, ArrHeading);
totalCount.then(function (resultantTotalCount) {
return contentCount = resultantTotalCount
});
// Here i want to use contentCount 10, But iam getting undefined
Thanks In advance

return contentCount = resultantTotalCount won't return the count, but rather the response of assignment. In contentCount = resultantTotalCount, you are basically assigning the value of resultantTotalCount to contentCount.
You should use
function moredbCount(contentMoreArray2, ArrHeading) {
var sampleArr = [];
for (var a = 0; a < contentMoreArray2.length; a++) {
if (ArrHeading !== 'More') {
var fullHeading = ArrHeading + '-' + contentMoreArray2[a].name;
} else {
fullHeading = contentMoreArray2[a].name;
}
sampleArr.push(fullHeading);
}
var sampleCount = sampleHeadingCount(sampleArr);
return sampleCount.then(function (resultantCount) {
return resultantCount; //Here iam getting some count like 10 and returning it to the function;
});
}
var contentCount;
var totalCount = moredbCount(contentMoreArray2, ArrHeading);
totalCount.then(function (resultantTotalCount) {
return resultantTotalCount
});

Javascript module programming

I'm study module programming.
take a look at below code:
var goodsspec = function(){
function setSpec(){
var
_price,
_storage,
defaultstats = true,
_val = '',
_resp = {
storage:".goods_stock",
price:".price"
}
$(".sys_item_spec .sys_item_specpara").each(function(){
var i = $(this);
var v = i.attr("data-attrval");
if(!v){
defaultstats = false;
}else{
val += _val!=""?"":"";
_val += v;
}
});
if(!!defaultstats){
_storage = sys_item['sys_attrprice'][_val]['goods_storage'];
_price = sys_item['sys_attrprice'][_val]['price'];
}else{
_storage = sys_item['goods_storage'];
_price = sys_item['price'];
}
$(_resp.storage).text( _storage);
$(_resp.price).text( _price);
if ( _storage == 0){
// Waring
}
}
return {
set:function(){
return setSpec();
}
};
}();
console.log(goodsspec.price);
I want to get _price and storage property value _value when I selected item.
How can I do this?

try something like
var Item = new Object();
function setSpec(){
// setting code
Item.price = _price;
Item.storage = _storage
}
then you could use
console.log("Prices is "+Item.price+" for "+Item.storage+".");

How does Javascript evaluate the right parenthesis?

I'm working on a calculator that takes an expression such as (5+4) and evaluates it by passing the buttons pressed to an array, and then building a parse tree from the data in the array.
What's interesting/strange, is that my code won't push the value of the right parenthesis to the array. Here is my code, could someone help me out?
The console.log activeButton shows that is the value of the button being pressed, but even when I placed calcArray.push() outside the if statements it would not push ) to an array.
$(document).ready(function(){
var calcArray = new Array();
$("input").click(function(){
var activeButton = this.value;
console.log(activeButton);
if(!isNaN(activeButton))
{
calcArray.push(parseInt(activeButton));
console.log(calcArray);
}
else if(activeButton === "=")
{
evaluate(buildTree(calcArray));
calcArray = [];
}
else
{
calcArray.push(activeButton);
}
});
});
The BuildTree code:
function BinaryTree(root) {
this.root = root;
this.activeNode = root;
}
function Node(element){
this.element = element;
this.parent;
this.rightChild;
this.leftChild;
this.setLeft = function(node){
this.leftChild = node;
node.parent = this;
};
this.setRight = function(node){
this.rightChild = node;
node.parent = this;
};
}
//methods
var buildTree = function(array)
{
var tree = new BinaryTree(new Node(null));
for(var i = 0; i < array.length; i++)
{
var newNode = new Node(array[i]);
if(array[i] == "(")
{
newNode.element = null;
tree.activeNode.setLeft(newNode);
tree.activeNode = newNode;
}
else if(array[i] == "+" || array[i] == "-" || array[i] == "/" || array[i] == "*")
{
tree.activeNode.element = newNode.element;
tree.activeNode.setRight(new Node(null));
tree.activeNode = tree.activeNode.rightChild;
}
else if(array[i] == ")")
{
if(tree.activeNode.parent == null)
{
;
}
else
{
tree.activeNode = tree.activeNode.parent;
tree.root = tree.activeNode;
}
}
else
{
tree.activeNode.element = newNode.element;
tree.activeNode = tree.activeNode.parent;
}
}
return tree.activeNode;
}
var evaluate = function(node){
var newNode1, newNode2;
newNode1 = new Node(null);
newNode1.parent = node;
newNode2 = new Node(null);
newNode2.parent = node;
if(node.leftChild == null && node.rightChild == null)
return node.element;
else{
newNode1.element = evaluate(node.leftChild);
newNode2.element = evaluate(node.rightChild);
if(newNode1.parent.element == "+")
{
return Number(newNode1.element) + Number(newNode2.element);
}
if(newNode1.parent.element == "-")
{
return newNode1.element - newNode2.element;
}
if(newNode1.parent.element == "*")
{
return newNode1.element * newNode2.element;
}
else
{
return newNode1.element / newNode2.element;
}
}
};

I just tried this out using your code and it worked fine passing the value as a string:
function pushButton (value) {
var activeButton = value;
console.log(activeButton);
if(!isNaN(activeButton))
{
calcArray.push(parseInt(activeButton));
console.log(calcArray);
}
else if(activeButton === "=")
{
evaluate(buildTree(calcArray));
calcArray = [];
}
else
{
calcArray.push(activeButton);
}
};
You aren't ever printing out the array in the last case (which is where the right paren would go), so are you sure it's not on the array and you just aren't seeing the visual feedback?
If so, we need to see more of your code. Try and setup a jsfiddle.

Dynamically building array, appending values

i have a bunch of options in this select, each with values like:
context|cow
context|test
thing|1
thing|5
thing|27
context|beans
while looping through the options, I want to build an array that checks to see if keys exist, and if they don't they make the key then append the value. then the next loop through, if the key exists, add the next value, comma separated.
the ideal output would be:
arr['context'] = 'cow,test,beans';
arr['thing'] = '1,5,27';
here's what i have so far, but this isn't a good strategy to build the values..
function sift(select) {
vals = [];
$.each(select.options, function() {
var valArr = this.value.split('|');
var key = valArr[0];
var val = valArr[1];
if (typeof vals[key] === 'undefined') {
vals[key] = [];
}
vals[key].push(val);
});
console.log(vals);
}

Existing code works by changing
vals=[];
To
vals={};
http://jsfiddle.net/BrxuM/

function sift(select) {
var vals = {};//notice I made an object, not an array, this is to create an associative array
$.each(select.options, function() {
var valArr = this.value.split('|');
if (typeof vals[valArr[0]] === 'undefined') {
vals[valArr[0]] = '';
} else {
vals[valArr[0]] += ',';
}
vals[valArr[0]] += valArr[1];
});
}
Here is a demo: http://jsfiddle.net/jasper/xtfm2/1/

How about an extensible, reusable, encapsulated solution:
function MyOptions()
{
var _optionNames = [];
var _optionValues = [];
function _add(name, value)
{
var nameIndex = _optionNames.indexOf(name);
if (nameIndex < 0)
{
_optionNames.push(name);
var newValues = [];
newValues.push(value);
_optionValues.push(newValues);
}
else
{
var values = _optionValues[nameIndex];
values.push(value);
_optionValues[nameIndex] = values;
}
};
function _values(name)
{
var nameIndex = _optionNames.indexOf(name);
if (nameIndex < 0)
{
return [];
}
else
{
return _optionValues[nameIndex];
}
};
var public =
{
add: _add,
values: _values
};
return public;
}
usage:
var myOptions = MyOptions();
myOptions.add("context", "cow");
myOptions.add("context","test");
myOptions.add("thing","1");
myOptions.add("thing","5");
myOptions.add("thing","27");
myOptions.add("context","beans");
console.log(myOptions.values("context").join(","));
console.log(myOptions.values("thing").join(","));
working example: http://jsfiddle.net/Zjamy/

I guess this works, but if someone could optimize it, I'd love to see.
function updateSiftUrl(select) { var
vals = {};
$.each(select.options, function() {
var valArr = this.value.split('|');
var key = valArr[0];
var val = valArr[1];
if (typeof vals[key] === 'undefined') {
vals[key] = val;
return;
}
vals[key] = vals[key] +','+ val;
});
console.log(vals);
}

Would something like this work for you?
$("select#yourselect").change(function(){
var optionArray =
$(":selected", $(this)).map(function(){
return $(this).val();
}).get().join(", ");
});
If you've selected 3 options, optionArray should contain something like option1, option2, option3.

Well, you don't want vals[key] to be an array - you want it to be a string. so try doing
if (typeof vals[key] === 'undefined') {
vals[key] = ';
}
vals[key] = vals[key] + ',' + val;