I am trying to send an information from one page to another through javascript file
the information will only contain a value of single variable.
how to accomplish this?I dont want to send it through query string as the value will be visible in the URL.
is there any other way?
You could save your data in LocalStorage and retrieve it on the other page.
localStorage.yourData = '{ test:"data" }';
console.log(localStorage['yourData']);
You have a few options to do that.
Depending on what browser is used, using localStorage is an option
//localStorage ONLY stores flat key:value pairs and can't contain Objects
localStorage.myString = "hello world";
localStorage.myObject = JSON.stringify({ foo: "bar" });
//Reading back the values is simple aswell
var myString = localStorage.myString;
var myObject = JSON.parse(localStorage.myObject);
Another method would be using a hash or query string. For example, you could redirect to www.yourdomain.com/your/path?myValue=1234
And then parse that by reading the search value from window.location.search (Will return ?myValue=1234 in that case) and splitting it on =:
var myValue = window.location.search.split("=")[1];
Another option is using hashes, similar to query params. Or even cookies.
BUT, all these methods will expose the value to the user, so if he wants to get that value, he will be able to!
At first, as other answers, use localStorage or sessionStorage to store global data.
Otherwise, you can add an event listener to detect the change of the storage value in your target page as follow:
window.addEventListener('storage', (e) => console.log(e.key, e.oldValue, e.newValue))
See: https://developer.mozilla.org/en-US/docs/Web/API/Web_Storage_API/Using_the_Web_Storage_API#Responding_to_storage_changes_with_the_StorageEvent
Related
Ok, so I have a database with data sets in it. the application performs a base API call to retrieve that base data set containing all other data sets. I will receive a string variable with the name of the key I need to access so let's say const addon = "Book". However, I don't know the key name beforehand. So the following code works but I need to somehow not hard code the key parameter but rather use the string value incoming from the const addon. I am not quite sure how to do this please point me to the right documentation or explain how to achieve the wanted result.
const columns = levelOne.Book && Object.keys(levelOne.Book);
However, as the incoming param might not be "Book" but anything else it will only work for this case. It is guaranteed that there is a key-value pair where the key bears the name stored in the string value of addon.
You can use a variable as the key. For example, levelOne[variable] where variable is the string that you want to use as the key.
Also, you can get the keys through Object.keys(levelOne) and then you can set variable value from the keys array.
I am running an old version of Angular - I have an object within my localStorage and I am trying to retrieve a single item from the object (rather than the whole the thing..)
var email = localStorage.user;
However the output of the localStorage.user variable is much longer (see below)- how would I retrieve the email address in this case 'bob#abc.com'?
{"firstname":"Bob","lastname":"Dole","id":"2000001999","accountId":"15","email":"bob#abc.com","instances":[{"name":"Test"}]}"
LocalStorage values are always stored as strings. In order to refer to the email in the object, we need to convert it to a JSON. We can do that by parsing the string using JSON.parse() method like below :
var email = JSON.parse(localstorage.user).email
You have Json structure not JS object, so parse it 1st
var email = JSON.parse(localStorage.user).email;
Using html5 local storage we can store data, add expire time by using cookies and sessions. https://stackoverflow.com/a/41385990/6554634 go through that, gives a lot of explanation
I've made users to enter some values in a html page:
Here is the code:
$(function() {
$("#savesymptoms").bind(
"click",
function() {
var url = "notes.html?acne="
+ encodeURIComponent($("#acne").val())
+ "&back="
+ encodeURIComponent($("#bloat").val());
window.location.href = url;
});
});
And I've added an alert like this:
alert("values passed");
But I'm not sure that this is working. I've got some 10 values to pass to another page. Above code contains only two values. Can I use arrays to pass all 10 values? I don't want to use nomenclature used in my code, i.e., individual value passing.
P.S: acne and bloat are the ids of the fields where user enters the data. notes.html is the page where I want to pass the data.
In my opinion you can use sessionStorage in HTML5
For setting a value
sessionStorage.setItem('name', 'value');
For getting the value:
sessionStorage.getItem('name');
if you want to store the value permanently use localStorage.
Since you have almost 10 values push all those values in a JSON and store it either in sessionStorage/localStorage.
You can retrieve it else where and use as per your wish
Note:values stored will be in the form of string even if you push it as JSON.You will have to make it to JSON using Jquery functions
Alternative
You can store it as window.name
But this will be only valid till the window lasts/tab closed(same as sessionStorage)
I have a multidimensional array that is something like this
[0]string
[1]-->[0]string,[1]string,[2]string
[2]string
[3]string
[4]-->[0]string,[1]string,[2]string[3]string,[4]string,[5]INFO
(I hope that makes sense)
where [1] and [4] are themselves arrays which I could access INFO like myArray[4][5].
The length of the nested arrays ([1] and [4]) can varry.
I use this method to store, calculate, and distribute data across a pretty complicated form.
Not all the data thats storred in the array makes it to an input field so its not all sent to the next page when the form's post method is called.
I would like to access the array the same way on the next page as I do on the first.
Thoughts:
Method 1:
I figure I could load all the data into hidden fields, post everything, then get those values on the second page and load themm all back into an array but that would require over a hundred hidden fields.
Method 2:
I suppose I could also use .join() to concatenate the whole array into one string, load that into one input, post it , and use .split(",") to break it back up. But If I do that im not sure how to handel the multidimensional asspect of it so that I still would be able to access INFO like myArray[4][5] on page 2.
I will be accessing the arrary with Javascript, the values that DO make it to inputs on page 1 will be accessed using php on page 2.
My question is is there a better way to acomplish what I need or how can I set up the Method 2 metioned above?
This solved my problem:
var str = JSON.stringify(fullInfoArray);
sessionStorage.fullInfoArray = str;
var newArr = JSON.parse(sessionStorage.fullInfoArray);
alert(newArr[0][2][1]);
If possible, you can use sessionStorage to store the string representation of your objects using JSON.stringify():
// store value
sessionStorage.setItem('myvalue', JSON.stringify(myObject));
// retrieve value
var myObject = JSON.parse(sessionStorage.getItem('myvalue'));
Note that sessionStorage has an upper limit to how much can be stored; I believe it's about 2.5MB, so you shouldn't hit it easily.
Keep the data in your PHP Session and whenever you submit forms update the data in session.
Every page you generate can be generated using this data.
OR
If uou are using a modern browser, make use of HTML5 localStorage.
OR
You can do continue with what you are doing :)
As shown in this example
javascript-use-variable-as-object-name
I am using eval to use a DOM attribute to select an element from an array. Though there is no direct way for the user to change the input, I want to be as secure as possible and make sure that the variable is indeed an integer before I evaluated it.
Which of the following would be the best, most secure, way?
$(".listitem").click(function(){
var id = $(this).attr("record-id");
if(!isNaN(new Number(id))){
Storage.search.nearby.currec = rowsHolder[eval(id)];
}else{
// send email to admin, shut down
}
});
or
$(".listitem").click(function(){
var id = $(this).attr("record-id");
if(parseInt(id)){
Storage.search.nearby.currec = rowsHolder[eval(id)];
}else{
// send email to admin, shut down
}
});
More, but not required info:
Basically I am pulling down a large JSON string from online, containing an array of records. Upon building a table from the info using a for statement ( for(i in array) ), I push each row into an array called rowsHolder and give the tr an attribute of record-id="i". Then when the user clicks the row, I call the method you see above. I am using PhoneGap with JQuery Mobile.
As always, thanks for the input
-D
There is absolutely no reason to use eval here.
If your id is kind of a number, use parseFloat(id) to get it. Unnecessary as it would be converted back to a string when used as a property name, though.
If your id is an integer, use parseInt(id, 10) to get it. Unnecessary as it would be converted back to a string when used as a property name, though.
If your id is a string, just let it be a string. The property name you use it for would be one anyway.