Javascript String to Object/Array - javascript

I have a javascript string which looks like this:
['Chris','Johannes','test','lag#a.deaaas','lag#a.deaaa','lag#a.eaaa','lag#a.ea']
I want to pass this to a php document as an array/object. What is the easiest (jQuery?) way to do this?
Edit: I grab this string from the DOM:
<div class="container" data-users="['Chris','Johannes','test','lag#a.deaaas','lag#a.deaaa','lag#a.eaaa','lag#a.ea']" data-userids="[1,2,3,12,13,15,16]">

First, convert the data-users and data-userids into JSON (see http://www.php.net/manual/en/function.json-encode.php). That means the all quotes must be double quotes ("").
<div class="container" data-users='["Chris","Johannes","test","lag#a.deaaas","lag#a.deaaa","lag#a.eaaa","lag#a.ea"]' data-userids='[1,2,3,12,13,15,16]'>
Then you can get the data like this:
var dataUsers = JSON.parse($('div.container').attr('data-users'))
// dataUsers[0], dataUsers[1], dataUsers.length ....
var dataUserIds = JSON.parse($('div.container').attr('data-userids'))

Use the jQuery data() function, which will automatically cast values to the correct javascript datatype, including arrays and objects:
var container = $('.container');
var users = container.data('users');
var userIds = container.data('userids');

Related

Array to Newline String to Array again through HTML

I have an array that comes in from from my API that I would like to arrange in a way that is better for the user (namely, in a column as opposed to the typical comma separated printed array).
This is my JS Fiddle to give a clearer picture: https://jsfiddle.net/2z89owas/
My question is, how can I get output3 to display just like output (and maintain its status as an iterable array like it was as dates)?
First you should not be using value for an html element. You can use .value for extracting value from inputs. Change your line to:
var val = document.getElementById('output2').innerHTML;
Afterwards, you have to split the same way you did join.
var dates3 = val.split('<br>');
document.getElementById('output3').innerHTML = dates3;
You can directly use join, something like:
document.getElementById('output3').innerHTML = dates.join(',');
You can try mapping over the contents of dates instead, as so:
let datesElem = dates.map(date =>`<p>${date}</p>`);
// test: console.log(datesElem)
document.getElementById('output3').innerHTML = datesElem

Expect Object but get String when parsing JSON

I am trying to parse a simple JSON string using jQuery
var parsedJSON = $.parseJSON('{"graph_data": "{}"}');
I would expect typeof(parsedJSON.graph_data) to be an Object but instead it is returning string. What is the correct way to return an Object?
It should be like
var parsedJSON = $.parseJSON('{"graph_data": {}}');
console.log(typeof(parsedJSON.graph_data));
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
no need of " for object, " is needed for defining string and object key. So it will treat as string here. For more about JSON structure and example visit http://www.json.org/.
try it.
var parsedJSON = $.parseJSON('{"graph_data": "{}"}');
console.log(parsedJSON.graph_data);

How to create an array with <input>?

I want to create an array with a html element. My main problem is, that i just get a string inside an array but no array.
Example: input is: 1,5,7,3,4
inside an array it look like this: ["1,5,7,3,4"] but i want it like this: [1,5,7,3,4]
I look for a solution made in javascript or better in jquery!
split will convert a string to an array.
var myArray = document.getElementById('myInput').value.split(',');
Use the split function to convert the string to an array.
For example:
<input type="text" id="myInput">1,5,7,3,4</input>
var myInput = $('#myInput').val();
var arr = myInput.split(','); // [1,5,7,3,4]

how to force jquery attr() to add the attribute with single quotes

I create an in memory div:
var video_div = document.createElement('div');
video_div.className = "vidinfo-inline";
In essence I have some variables:
var key = "data-video-srcs";
var value = '{"video1":"http://www.youtube.com/watch?v=KdxEAt91D7k&list=TLhaPoOja-0f4","video2":"http://www.youtube.com/watch?v=dVlaZfLlWQc&list=TLalXwg9bTOmo"}';
And I use jquery to add that data attribute to the div:
$(video_div).attr(key, value);
Here is my problem. After doing that I get this:
<div class="vidinfo-inline" data-video-srcs="{"video1":"http://www.youtube.com/watch?v=KdxEAt91D7k&list=TLhaPoOja-0f4","video2":"http://www.youtube.com/watch?v=dVlaZfLlWQc&list=TLalXwg9bTOmo"}"></div>
And that doesn't work putting that json in there. It has to be in single quotes. It has to look like this:
<div class="vidinfo-inline" data-video-srcs='{"video1":"http://www.youtube.com/watch?v=KdxEAt91D7k&list=TLhaPoOja-0f4","video2":"http://www.youtube.com/watch?v=dVlaZfLlWQc&list=TLalXwg9bTOmo"}'></div>
As later on I do something like this:
var video_srcs = $('.vidinfo-inline').data('video-srcs');
And that won't work unless the json is in single quotes.
Does anyone have any ideas?
EDIT:
According to jquery: http://api.jquery.com/data/#data-html5
When the data attribute is an object (starts with '{') or array (starts with '[') then jQuery.parseJSON is used to parse the string; it must follow valid JSON syntax including quoted property names. If the value isn't parseable as a JavaScript value, it is left as a string.
Thus I can't escape the double quotes, it has to be inside single quotes. I have a work around and I'll post that as an answer unless someone else has a better answer.
I have a workaround. And if anyone has a better solution, I'd love to see it.
I wrote a replace method:
var fixJson = function(str) {
return String(str)
.replace(/"{/g, "'{")
.replace(/}"/g, "}'");
};
So basically I send the html into this function and insert it into the DOM.
For example:
var html = htmlUnescape($('#temp_container').html());
html = fixJson(html);
I realize that has some code smell to it. I mean, going through everything on that element just to fix the double quotes to single quotes stinks. But for lack of other options or ideas, it works. :\
Replace the double quotes with HTML entities:
var value = '{"video1":"http://www.youtube.com/watch?v=KdxEAt91D7k&list=TLhaPoOja-0f4","video2":"http://www.youtube.com/watch?v=dVlaZfLlWQc&list=TLalXwg9bTOmo"}';
# Naive approach:
value = value.replace('&', '&').replace('"', '"');
# Using jQuery:
var $tmp = jQuery('<div></div>');
value = $tmp.text(value).html();
// Then store it as normal

Why is my .data() function returning [ instead of the first value of my array?

I want to pass an array into a jQuery data attribute on the server side and then retrieve it like so:
var stuff = $('div').data('stuff');
alert(stuff[0]);
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/1.6.1/jquery.min.js"></script>
<div data-stuff="['a','b','c']"></div>
Why does this appear to alert '[' and not 'a' (see JSFiddle link)
JSFiddle Link: http://jsfiddle.net/ktw4v/3/
It's treating your variable as a string, the zeroth element of which is [.
This is happening because your string is not valid JSON, which should use double-quotes as a string delimiter instead of single quotes. You'll then have to use single-quotes to delimit the entire attribute value.
If you fix your quotation marks your original code works (see http://jsfiddle.net/ktw4v/12/)
<div data-stuff='["a","b","c"]'> </div>
var stuff = $('div').data('stuff');
When jQuery sees valid JSON in a data attribute it will automatically unpack it for you.
Declaring it as an attribute means that it is a string.
So stuff[0] would be equivalent to: var myString = "['a','b','c']"; alert(myString[0]);
You need to make it look like this:
<div data-stuff="a,b,c"></div>
var stuff = $('div').data('stuff').split(',');
alert(stuff[0]);
Retraction: jQuery's parsing fails because it didn't meet the rules of parseJSON.
However, I will stand behind my solution. There are aspects of the others that are less than ideal, just as this solution is less than ideal in some ways. All depends on what your paradigms are.
As others have identified the value is treated as string so it is returning "[". Please try this (aaa is the name of the div and I took out the data-stuff):
$(function(){
$.data($("#aaa")[0],"stuff",{"aa":['a','b','c']});
var stuff = $.data($("#aaa")[0],"stuff").aa;
alert(stuff[0]); //returns "a"
});
A different approach is posted at jsfiddle; var stuff = $('div').data('stuff'); stuff is a string with 0th character as '['
Well, var stuff = eval($('div').data('stuff')); should get you an array

Categories