LocalStorage string always returning undefined JS - javascript

My localStorage string is always returning undefined, no matter what I do? I need help.
Related code snippets:
if (window.localStorage.firstVisit !== "false") {
window.localStorage.score = 0;
window.localStorage.name = "";
var origScore = parseInt(window.localStorage.score, 10);
window.localStorage.name;
} else {
var origScore = parseInt(window.localStorage.score, 10);
window.localStorage.name;
}
window.localStorage.firstVisit = "false";
var e = 0;
var fallenHuman = window.localStorage.name;
...
console.log(fallenHuman);
window.localStorage.name = fallenHuman;
var fallenHuman = window.localStorage.name;
document.getElementById("namesh").innerHTML = fallenHuman + " - Click to change";

From the looks of it, it looks like you are not using localStorage correctly. You are setting properties on the localStorage object, not actually in localStorage.
Secondly, you have something like this, which doesn't make any sense:
var fallenHuman = window.localStorage.name;
console.log(fallenHuman);
window.localStorage.name = fallenHuman;
You are just setting itself to ...itself. fallenHuman and window.localStorage.name are the exact same thing at all times. This code does nothing.
Example of working with localStorage from the docs
Sets an item in localStorage
localStorage.setItem('myCat', 'Tom');
Gets an item from localStorage
var cat = localStorage.getItem('myCat');
I've never actually seen anyone use localStorage in a way that you're using it, but I can assure you, that is not the intended usage of localStorage.
Unrelated your actual issue: you can probably drop window from all your code. You should be able to just do localStorage.* and be fine. I'm not sure what your setup is, so if that doesn't work, disregard this.

Related

how to get single value by cookie in java script

java script code is store cookie
document.cookie = 'CookieName='+'grid';
i want to get CookieName value grid i haveto store many cookie but i get this one this cookie store at the first index in cookie
$( document ).ready(function() {
var CookieName=document.cookie;
if(CookieName =='grid')
{
$('#tab_b').hide();
$('#tab_a').show();
}
else {
$('#tab_a').hide();
$('#tab_b').show();
}
});
how to get CookieName value
I got the impression that you found the answer by Jay Blanchard too long, so I'll provide a shorter alternative. But first let me say something else. As a comment to Jay Blanchard's answer, you wrote:
thanks bro i have got it and very simple and short function check it var allcookies = document.cookie; cookiearray = allcookies.split(';'); name = cookiearray[0].split('=')[0]; value = cookiearray[0].split('=')[1];
However, I highly recommend you rethink that as this assumes CookieName is always the first cookie. (Someone might say "but I will somehow make sure it always is", but the point is, this is key/value, not array, so the approach is conceptually wrong and confusing, or as they say, bad practice).
Now, for the code:
var cookieValue = document.cookie.replace(/(?:(?:^|.*;\s*)CookieName\s*\=\s*([^;]*).*$)|^.*$/, "$1");
This is something I have blantantly stolen from the MDN page on cookies which I highly recommend if you want to learn more about cookies.
I have written a small function (I could probably make this much more efficient, but I have used it for a long time) which should work for you:
function getCookieAttr(attribute) {
var attr = attribute + "="; // create an attribute string
var parts = document.cookie.split(';'); // split the cookie into parts
for(var i = 0; i <parts.length; i++) { // loop through the parts for each item
var item = parts[i];
while (item.charAt(0)==' ') { // account for spaces in the cookie
item = item.substring(1); // set the item
}
if (item.indexOf(attr) == 0) { // if the item matches the attribute
return item.substring(attr.length,item.length); // return the value
}
}
return "";
}
To use the function pass the attribute name:
document.cookie = "CookieName=grid";
console.log(getCookieAttr('CookieName'));

textContent Vs. innerText Cross Browser solution

I've been having a hard time with cross browser compatibility and scrapping the dom.
I've added data analytics tracking to ecommerce transactions in order to grab the product and transaction amount for each purchase.
Initially I was using document.querySelectorAll('#someId')[0].textContent to get the product name and that was working fine for every browser except internet explorer.
It took some time to figure out that it was the .textContent part that was causing ie problems.
Yesterday I changed .textContent to .innerText. From looking inside analytics it seems that the issue has been resolved for ie but now Firefox is failing.
I was hoping to find a solution without writing an if statement to check for the functionality of .textContent or .innerText.
Is there a cross browser solution .getTheText?
If not what would be the best way around this? Is there a simple solution? (I ask given my knowledge and experience with scripting, which is limited)
** added following comments **
If this is my code block:
// build products object
var prods = [];
var brand = document.querySelectorAll('.txtStayRoomLocation');
var name = document.querySelectorAll('.txtStayRoomDescription');
var price = document.querySelectorAll('.txtStayRoomSplashPriceAmount');
for(var i = 0; i < brand.length; i++) {
//set granular vars
var prd = {};
//add to prd object
prd.brand = brand[i].innerText;
prd.name = name[i].innerText;
prd.price = price[i].innerText;
prd.quantity = window.session_context_vars.BookingContext.Booking.ReservationLineItems[i].ReservationCharges.length/2;;
//add to prods array
prods.push(prd);
}
Then if I understand the syntax from the comments and the question linked to in the comment, is this what I should do:
// build products object
var prods = [];
var brand = document.querySelectorAll('.txtStayRoomLocation');
var name = document.querySelectorAll('.txtStayRoomDescription');
var price = document.querySelectorAll('.txtStayRoomSplashPriceAmount');
for(var i = 0; i < brand.length; i++) {
//set granular vars
var prd = {};
//add to prd object
prd.brand = brand[i].textContent || brand[i].innerText;
prd.name = name[i].textContent || name[i].innerText;
prd.price = price[i].textContent || price[i].innerText;
prd.quantity = window.session_context_vars.BookingContext.Booking.ReservationLineItems[i].ReservationCharges.length/2;;
//add to prods array
prods.push(prd);
}
So using or with a double bar || assigns the first non null value?
Re: your edit, not quite. The way to access methods or properties on an object (eg a DOM element) is to use dot notation if you have the name itself, or square brackets in case of variables/expressions (also works with strings, as in obj["propName"], which is equivalent to obj.propName). You can also just test the property against one element and use that from there on:
// build products object
var prods = [];
var brand = document.querySelectorAll('.txtStayRoomLocation');
var name = document.querySelectorAll('.txtStayRoomDescription');
var price = document.querySelectorAll('.txtStayRoomSplashPriceAmount');
for(var i = 0; i < brand.length; i++) {
//set granular vars
var prd = {};
//add to prd object
var txtProp = ("innerText" in brand[i]) ? "innerText" : "textContent"; //added string quotes as per comments
prd.brand = brand[i][txtProp];
prd.name = name[i][txtProp];
prd.price = price[i][txtProp];
prd.quantity = window.session_context_vars.BookingContext.Booking.ReservationLineItems[i].ReservationCharges.length/2;;
//add to prods array
prods.push(prd);
}
Regarding the line:
var txtProp = (innerText in brand[i]) ? innerText : textContent;
The in keyword checks an object to access the property (syntax: var property in object). As for the question notation (I made an error earlier, using ||, the correct thing to use was a :),
var myVar = (prop in object) ? object[prop] : false;
As an expression, it basically evaluates the stuff before the ?, and if it's true, returns the expression before the :, else the one after. So the above is the same as / a shorthand for:
if(prop in object){
var myVar = object[prop];
}
else{
var myVar = false;
}
Since you are checking between two properties only and wanting to assign one or the other, the shortest way would indeed be:
var txtProp = brand[i].innerText || brand[i].textContent;
It would basically test the first property, and if it were false or undefined, it would use the second one. The only reason I (pedantically) avoid using this is because the first test of a || b would fail even if a existed but just had a value of 0, or an empty string (""), or was set to null.

Backbonejs variable in a where filter key

Just wondering if anyone knows why I can't get both key/values within a 'where' to be dynamic? I can do the value through a variable, that works perfectly, but I can't seem to get the key to run off a variable at all.
My fiddle is here: http://jsfiddle.net/leapin_leprechaun/eyw6295q/ the code I'm trying to get working is below.
I'm new to backbone so there's a chance this is something you can't do and I just don't know about it yet!
var newCollection = function(myCollection,prop,val){
alert('myprop: ' + prop);
alert('val: ' + val);
var results = myCollection.where({
//prop: val this doesn't work even if I put a string above it to make sure the value coming through is fine
//prop: "Glasnevin" //this doesn't work
"location" : val //this works
});
var filteredCollection = new Backbone.Collection(results);
var newMatchesModelView = new MatchesModelView({collection: filteredCollection });
$("#allMatches").html(newMatchesModelView.render().el);
}
Thanks for your time
Your code does not work because the key "prop" is always interpreted literally, as a string. So, you search by {"prop": val} not by {"location": val}. There are couple ways how to solve this problem
1
var where = {};
where[prop] = val;
var results = myCollection.where(where);
2
var results = myCollection.where(_.object([prop], [val]));
There are a few ways to do this, the simplest would be to just create a placeholder object, and assign the key and value:
var query = {};
query[prop] = val;
var results = myCollection.where(query);
Or, if that's too verbose and you are alright with a very small amount of overhead, you could use _.object
var results = myCollection.where(_.object([prop], [val]);

How to get the next element of an array with Jquery onclick

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;
});

Global var in JavaScript

This is annoying me.
I'm setting an array in beginning of the doc:
var idPartner;
var myar = new Array();
myar[0] = "http://example.com/"+idPartner;
And I'm getting a number over the address, which is the id of partner. Great. But I'm trying to set it without success:
$.address.change(function(event) {
idPartner = 3;
alert(idPartner);
}
Ok. The alert is giving me the right number, but isn't setting it.
What's wrong?
Changing the value of the variable does not re-set the values within the array. That is just something javascript can't do automatically. You would have to re-generate the array for it to have the new id. Could you add the id to the value where you use the array instead of pre-setting the values in the array containing the id?
Edit: For example, you would do:
var myArray = [];
var myId = 0;
myArray[0] = "http://foo.com/id/";
and when you need to use a value from the array, you would do this:
var theVal = myArray[0] + myId;
Try this:
var myvar = ["http://site.com/"];
$.address.change(function(event) {
myvar[1] = 3;
}
then use myvar.join () where you need the full url.
The problem here is that at the line
myar[0] = "http://site.com/"+idPartner;
..you perform a string concatenation, meaning you copy the resulting string into the array at index position 0.
Hence, when later setting idPartnerit won't have any effect on the previously copied string. To avoid such effect you can either always construct the string again when the idPartnervariable updates or you create an object and you evaluate it when you need it like...
var MyObject = function(){
this.idPartner = 0; //default value
};
MyObject.prototype.getUrl = function(){
return "http://site.com/" + this.idPartner;
};
In this way you could use it like
var myGlblUrlObj = new MyObject();
$.address.change(function(event){
myGlblUrlObj.idPartner = ... /setting it here
});
at some later point you can then always get the correct url using
myGlblUrlObj.getUrl();
Now obviously it depends on the complexity of your situation. Maybe the suggested array solution might work as well, although I prefer having it encapsulated somewhere in an object for better reusability.
myar[0] = "http://site.com/" + idPartner;
After this line, myar[0] = "http://site.com/undefined" and it has nothing to do with the variable idPartner no more.
So, after that changing the value of idPartner will affect the value of myar[0].
You need to change the value of myar[0] itself.

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