Develop Reference

How to properly read array from a data table on Code.Org AppLab?

I created a table called "morning" in AppLab, and one column stores data as an array (or list as it calls it). I'm able to properly add data to this array, but my problem is reading the data back (as I want to display it as a label/normal text on another page) If the numbers 1234 and 5678 are the values in the array, when I try to do
console.log(records[i].id + ': ' + records[i].buses);
The second value (buses) is the name of the column I'm trying to read back, which will result in "," rather than "1234,5678" and I'm not really sure what to do. This is the code I have so far, any help would be greatly appreciated!
readRecords("morning", {}, function(records) {
for (var i =0; i < records.length; i++) {
console.log((records[i]).id + ': ' + records[i].(buses[i]));
}
});
var ts1Buses = ["1234"];
var ts1Change;
onEvent("enterTS1", "click", function(event) {
appendItem(ts1Buses, getText("textTS1"));
updateRecord("morning", {id:1, buses:ts1Buses}, function(record, success) {
setText("textTS1", "");
});
});

The console.log statement in your longer block of code doesn't look quite right. try console.log(records[i].id + ': ' + records[i].buses); instead. if that doesn't work, please post a link to your project so that others can try to find a fix by remixing and editing it.

App Lab's data tables do not support arrays. They will have to be converted into comma-separated strings before creating or updating and converted to an array after reading.
To convert an array to a string, simply use the toString() method:
var array = ["a", "b", "c"];
console.log(array.toString()) // "a,b,c"
To convert a string into an array, use the split() method:
var string = "a,b,c";
console.log(string.split(","); // ["a", "b", "c"]

How to split into valid array

I've following object that is return from API and I want to convert them into array either in javascript or c#.
[
"1":"h1:first",
"2":".content a > img",
"3":"#content div p"
]
I've tried converting that to json object, split function etc but din't working for me.
It throws exception Uncaught SyntaxError: Unexpected token : while using split function in javascript.

You can convert it to valid JSON by replacing the square brackets with curly braces.
var data = '["1":"h1:first","2":".content a > img","3":"#content div p"]';
var json = `{ ${data.trim().slice(1, -1)} }`;
Then JSON.parse it like you had tried earlier. And if you want an array, and don't care about the actual index numbers, you can use Object.values to get the Array of values.
var data = '["1":"h1:first","2":".content a > img","3":"#content div p"]';
var json = `{ ${data.trim().slice(1, -1)} }`;
console.log(json);
var parsed = JSON.parse(json);
console.log(parsed);
var array = Object.values(parsed);
console.log(array);

I choose c# code to fix the issue instead client-side (as suggested by #rock star below).
string[] domSelectors = selectors.Replace("\"", "").Split(new string[] { "[", ",", "]" }, StringSplitOptions.RemoveEmptyEntries);
foreach (var domSelector in domSelectors)
{
string[] arrayElements = domSelector.Split(':');
string selector = string.Join(":", arrayElements.Skip(1));
}
Hope it helps others who don't have control over API and want to fix the issue as I'd in my project!

Parsing JSON and loading into array

JSON-https://www.alphavantage.co/query?function=TIME_SERIES_DAILY&symbol=MSFT&apikey=demo
I am trying to take the JSON from the above link and place it in the following format(date,open,high,low,close)...
[
[1277424000000,38.58,38.61,37.97,38.10],
[1277683200000,38.13,38.54,37.79,38.33],
[1277769600000,37.73,37.77,36.33,36.60],
[1277856000000,36.67,36.85,35.72,35.93],
]
The date does not need to be Epoch time.
My code....
$.getJSON('https://www.alphavantage.co/query?
function=TIME_SERIES_DAILY&symbol=MSFT&apikey=demo', function(data) {
//Get the time series data
var timeseries = data['Time Series (Daily)']
var ohlcarray = [];
//Loop through each time series and convert it to JSON format
$.each(timeseries, function(key, value) {
var ohlcdata=[];
ohlcdata[0]=value[0];//date
ohlcdata[1]=value[1];//open
ohlcdata[2]=value[2];//high
ohlcdata[3]=value[3];//low
ohlcdata[4]=value[4];//low
ohlcarray.push(ohlcdata);
});
console.log(ohlcarray[0]);//test if worked properly
});
The output....
[undefined, undefined, undefined, undefined, undefined]
value[x] returns undefined. Any ideas on why this happens?
Thanks!

The reason is that in the each loop, the value is not a list but an object. To access it, you'd have to grab it using keys.
ohlcdata[0] = key; //date
ohlcdata[1] = value['1. open']; //open
ohlcdata[2] = value['2. high']; //high
ohlcdata[3] = value['3. low']; //low
ohlcdata[4] = value['4. close']; //low
https://jsfiddle.net/koralarts/7c2fkf93/2/

At this point it is already JSON. As Patrick mentioned, getJSON automatically parses json. You will need to access it with the array bracket notation since there are spaces in the property name.
var timeSeries = data['Time Series (Daily)'];
See ex: https://jsfiddle.net/dz0phhn2/6/

set array as value in json format in Javascript

I want to add array as json value.
Json format is as follows.
json_data = [
'name':'Testing'
'email':'TestEmail'
'links':[
'test#test.com',
'test#test1.com',
'test#test3.com']
]
How can I set value of 'links' in javascript like that?
I did as follows.
links_array = [];
links_array =['testing','test2'];
json_data.links = links_array;
I wanted to append these two string but couldn't.
Any help would be appreciate.

Assuming that the syntax of your example is correct, you can use the "push" method for arrays.
json_data = {
'name':'Testing',
'email':'TestEmail',
'links':[]
};
json_data.links.push("test1#test.com");
json_data.links.push("test2#test.com");
json_data.links.push("test3#test.com");

You have to make little changes to make it work.
First thing, You have to replace initial square brackets with curly one. By doing this your object will become JSON Literal - a key value pair.
Second thing, You have missed commas after 'name':'Testing' and 'email':'TestEmail'
Below will work perfectly:
var json_data = {
'name':'Testing',
'email':'TestEmail',
'links':[
'test#test.com',
'test#test1.com',
'test#test3.com']
}

In addition to push as mentioned by #giovannilobitos you can use concat and do it all in one go.
var json_data = {
'name':'Testing',
'email':'TestEmail',
'links':[
'test#test.com',
'test#test1.com',
'test#test3.com'
]
};
var links_array = ['testing','test2'];
json_data.links = json_data.links.concat(links_array);
console.log(json_data.links);
On MDN's array reference you can find a more complete list of how to modify arrays in JavaScript.

covert large array of objects into smaller array objects using javascript

I have an list of values like this from a sql database.
UserName Email ComputerName DateIssued
jjsmith jjsmith#example.com JTComputer 9/14/2013
ltjoseph ltjoseph#example.com LTComputer1 10/21/2013
KTsmith KevinTem#example.com KTComputer1 01/25/2012
ltjoseph ltjoseph#example.com LTComputer2 01/11/2013
KTsmith KevinTem#example.com KTComputer2 01/25/2012
I transform my list into an array of objects.
var user_array = [
{"username":"jjsmith", "email":"jjsmith#example.com", "computerName":"JTComputer", "dateissued":"10/21/2013"}
{"username":"ltjoseph", "email":"ltjoseph#example.com", "computerName":"LTComputer1", "dateissued":"10/21/2013"}
{"username":"KTsmith", "email":"KevinTem#example.com", "computerName":"KTComputer1", "dateissued":"01/25/2012"}
{"username":"ltjoseph", "email":"ltjoseph#example.com", "computerName":"LTComputer2", "dateissued":"01/11/2013"}
{"username":"KTsmith", "email":"KevinTem#example.com", "computerName":"KTComputer2", "dateissued":"01/25/2012"}]
A function has been created by someone else that sends emails to users, it only accepts two parameters which are strings.
So I don't want to send more than 1 email per user. So I am trying to figure out how to combine the items together so that my an example set of strings look like this.
var str1 = "ltjoseph#example.com";
var str2 = "ltjoseph, LTComputer1-10/21/2013, LTComputer2-01/11/2013";
and then fire the other user function to send emails for each of the items in the list.
function sendEmails(str1, str2);
If anyone has any ideas how i can do this. Please advise..

var by_user = {};
for (var i = 0; i < user_array.length; i++) {
if (by_user[user_array[i].username]) {
// Found user, add another computer
by_user[user_array[i].username].str2 += ', ' + user_array[i].computerName + '-' + user_array[i].dateissued;
} else {
// First entry for user, create initial object
by_user[user_array[i].username] = {
str1: user_array[i].email,
str2: user_array[i].username + ', ' + user_array[i].computerName + '-' + user_array[i].dateissued
};
}
}
Now you have the by_user object, which has a single sub-object for each user, whose str1 and str2 properties are the variables you want.
by_user['ltjoseph'].str1 => ltjoseph#example.com
by_user['ltjoseph'].str2 => ltjoseph, LTComputer1-10/21/2013, LTComputer2-01/11/2013

something like this:
var str1=array[0].email
var str2=array[0].username+", "+array[0].computerName+array[0].dateissued
or use a loop and iterate through the array

I strongly recommend bringing in a library like lodash for this sort of thing and using uniq (sample here: http://jsfiddle.net/MwYtU/):
var uniqs = lodash(user_array).pluck('email').uniq().value();
If you're doing javascript and aren't acquainted with lodash or underscore, go do that because it'll save you a lot of time. Using tried and true code is a good idea. Added bonus: if you want to see how the pros are doing something like uniq you can just look at the source code.