Develop Reference

How can I use underscore in name of dynamic object variable

Website that I'm making is in two different languages each data is saved in mongodb with prefix _nl or _en
With a url I need to be able to set up language like that:
http://localhost/en/This-Is-English-Head/This-Is-English-Sub
My code look like that:
var headPage = req.params.headPage;
var subPage = req.params.subPage;
var slug = 'name';
var slugSub = 'subPages.slug_en';
var myObject = {};
myObject[slugSub] = subPage;
myObject[slug] = headPage;
console.log(myObject);
Site.find(myObject,
function (err, pages) {
var Pages = {};
pages.forEach(function (page) {
Pages[page._id] = page;
});
console.log(Pages);
});
After console.log it I get following:
{ 'subPages.slug_en': 'This-Is-English-Sub',
name: 'This-Is-English-Head' }
Is you can see objectname subPages.slug_en is seen as a String insteed of object name..
I know that javascript does not support underscores(I guess?) but I'm still looking for a fix, otherwise i'll be forced to change all underscores in my db to different character...
Edit:
The final result of console.log need to be:
{ subPages.slug_en: 'This-Is-English-Sub',
name: 'This-Is-English-Head' }
Insteed of :
{ 'subPages.slug_en': 'This-Is-English-Sub',
name: 'This-Is-English-Head' }
Otherwise it does not work

The reason you are seeing 'subPages.slug_en' (with string quotes) is because of the . in the object key, not the underscore.
Underscores are definitely supported in object keys without quoting.
Using subPages.slug_en (without string quotes) would require you to have an object as follows:
{ subPages: {slug_en: 'This-Is-English-Sub'},
name: 'This-Is-English-Head' }
Which you could set with the following:
myObject['subPages']['slug_en'] = subPage;
Or simply:
myObject.subPages.slug_en = subPage;

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.

Add [DataObject] to exsisting array with var key

Using Cordova, I am trying to get an Object to add to an array. I have this working on node JS using :
theData = {[varkey]:DataObject};
But I can't get this to work the same way within my javascript that cordova runs.
I need to do the following:
var TownName = 'Auckland', var townData = (JSON Data);
theArray = new Array();
theArray[TownName] = townData;
I need to be able to call it back as:
theArray['Auckland']
Which will return (JSON Data)
But it doesn't want to store the data with the key inside the array.
I have also tried:
theArray.TownName = townData;
theArray = [{TownName:townData}];
theArray = {[TownName]:townData}];
Nothing wants to store the data.
Any suggestions?
::EDIT::
data.theData =
"Auckland"[
{
"username":"pndemoname1",
"number":"373456",
"www":"http://373456.pndemoname1",
"icon":"/imgs/pndemoname1.png"
},
{
"username":"pndemoname2",
"number":"373458",
"www":"http://373458.pndemoname2",
"icon":"/imgs/pndemoname2.png"
}
data.town = "Auckland";
townData = new Array();
alert(JSON.stringify(data.theData))//Alerts theData
townData[data.town] = data.theData
alert(townData[townName]) //Alerts undefined
::EDIT2::
Re-defining the array within the function that deals with all of the data, seems to make it work.
As per my answer, the issue was that I assumed javascript vars are global.

Use objects or an array of objects.
A data structure like this:
{
town1: town1Data,
town2: town2Data,
}
Or more common:
[
{
name: "Town 1",
data: {...}
},
{
name: "Town 2",
data: {...}
},
]
For reference:
http://andrewdupont.net/2006/05/18/javascript-associative-arrays-considered-harmful/

I got what you're trying to do, to add property names dynamically to your object is first, by making sure you are using an OBJECT instead of an array, so when you want to store something you will do the following:
var _obj = {}, _something = 'xyz';
_obj[ _something ] = { ... }; // json structure
The problem you're facing is that you want to assign a string value as a key inside your array, which will not work.
However, you can still use the array you defined and do the following:
var _array = new array();
_array.push( { .... } ); // insert json structure
Remember! By using the array you will have to loop through all values every time you want to access your key, just as the best practice to avoid getting into errors.
Good luck.

The issue was that I didn't define the array within the function of where I was trying to add the information to.
I assumed the var was global (Too much PHP)

Turn Observable Array into nested JSON

I'm having a problem getting an array of information stored properly as JSON.
I made a fiddle to illustrate the problem. Enter a set of tags and take a look at the console to see the output.
More explanation:
So I have an input that takes in a comma-separated list of tags, which I then format.
function createTagArray() {
// given an input value of 'tag1, tag2, tag3'
// returns array = ['tag1', 'tag2', 'tag3']
}
I thought what I needed to do next was the following:
loop over the array and create a 'tag' object for each item which also includes an id for the tag and the id of the contact the tag is associated with.
Each object is pushed to tags, an observable array.
function single_tag(id, contactId, tagLabel) {
var self = this;
self.id = id;
self.contactId = contactId;
self.tagLabel = tagLabel;
}
function createTags() {
var array = createTagArray();
for (var i = 0; i < array.length; i++) {
self.tags().push(new single_tag(uuid.generate(), self.contactId, array[i]));
}
}
Then, I converted it into JSON
self.contactInformation = function() {
return ko.toJS({
"id": self.contactId,
"firstname": self.firstname(),
"lastname": self.lastname(),
... other fields ...
"tags": self.tags(),
})
}
But, when I inspect the console output of calling this function, tags is a collection of arrays, not a nice json object.
How do I get it formatted correctly?
I tried this suggestion, and the tag json is structured correctly, but it is stored with escaped quotes, so that seems wrong.
Thanks for all the help!

I would recommend you knockout.mapping plugin for KO, it allow map complicated JSON structure to view model, even without declarations.
From the documentation
Let’s say you have a JavaScript object that looks like this:
var data = {
name: 'Scot',
children: [
{ id : 1, name : 'Alicw' }
]
}
You can map this to a view model without any problems:
var viewModel = ko.mapping.fromJS(data);
Now, let’s say the data is updated to be without any typos:
var data = {
name: 'Scott',
children: [
{ id : 1, name : 'Alice' }
]
}
Two things have happened here: name was changed from Scot to Scott and children[0].name was changed from Alicw to the typo-free Alice. You can update viewModel based on this new data:
ko.mapping.fromJS(data, viewModel);
And name would have changed as expected. However, in the children array, the child (Alicw) would have been completely removed and a new one (Alice) added. This is not completely what you would have expected. Instead, you would have expected that only the name property of the child was updated from Alicw to Alice, not that the entire child was replaced!
...
To solve this, you can specify which key the mapping plugin should use to determine if an object is new or old. You would set it up like this:
var mapping = {
'children': {
key: function(data) {
return ko.utils.unwrapObservable(data.id);
}
}
}
var viewModel = ko.mapping.fromJS(data, mapping);

In the jsfiddle you were using Knockout 3.0 which doesn't have support for textInput. This was added in 3.2. To use version 3.2 you need to use a cdn such as this: http://cdnjs.com/libraries/knockout
There was typeo in your binding. sumbit should be submit.
There was a problem with your constructor for single_tag. id was not used so I removed it:
function single_tag(contactId, tagLabel) {
var self = this;
self.contactId = contactId;
self.tagLabel = tagLabel;
}
Currently also contactId is not set because the observable has not been set to a value.
To convert to JSON you need to use ko.toJSON instead of ko.toJS:
self.contactInformation = function() {
return ko.toJSON({
"firstname": self.firstname(),
"tags": self.tags(),
})
}
Now when the console writes out an array appears:
{
"firstname":"test",
"tags":[
{"tagLabel":"test1"},
{"tagLabel":"test2"},
{"tagLabel":"test3"}
]
}
JsFiddle

So my problem was more basic than I was realizing. I'm using JSON Server to serve up my data, and I was pulling information from two parts of the database (contacts & tags).
When I tried to update my tags, I was trying to apply them to a property that didn't exist on the contact JSON in my database. Posting the tags separately worked though.

Using variable keys to access values in JavaScript objects

The code:
function updateDashboardData() {
$.getJSON("includes/system/ajaxDataInterface.php", {recordcount:1}, function(data) {
$('.stationContainer').each(function(data) {
var bsID = $(this).attr("id");
var bsStatus = $(this).children('.stationStatus');
alert(data[bsID][0].time);
bsStatus.find('.bs_maxHandsets').text(data[bsID][0].maxHandsets);
bsStatus.find('.bs_time').text(data[bsID][0].time);
});
});
}
The object data:
{
"A5A50000": [{
"bsid": "A5A50000",
"chanCount": 17,
"time": "2009-05-27 16:36:45",
"avgInterference": 1.711765,
"maxInterference": 4.97,
"avgHandsets": 205.1176,
"maxHandsets": 315,
"avgCalls": 6.4118,
"maxCalls": 13,
"avgCBA": 3868.98059,
"maxCBA": 7463,
"sumSuccessCBA": 197318,
"sumTimeoutHandoff": 133,
"sumAttemptHandoff": 1028,
"sumDeniedHandoff": 216,
"sumConfirmHandoff": 679,
"sumHandoffNetwork": 61873,
"sumJoinNetwork": 96888,
"sumLeaveNetwork": 93754,
"sumRcvdKeepalive": 98773,
"sumTimeoutKeepalive": 19748,
"sumAttemptUplink": 93689,
"sumBlockedUplink": 62453
}]
}
The problem:
alert(data.A5A50000[0].time); properly displays "2009-05-27 16:36:45".
alert(bsID); properly displays "A5A50000".
alert(data.bsID[0].time); reports "data.bsID is undefined".
alert(data[bsID][0].time); reports "data[bsID] is undefined".
I'm a little unclear when a variable is/isn't evaluated. Maybe I'm overlooking something silly, but I can't figure out my problem here.

You can access object properties by dot notation or by bracket notation.
var x = {'test': 'hi'};
alert(x.test); // alerts hi
alert(x['test']); // alerts hi
When you have a dynamic value, you have to use the latter:
var property = 'test';
alert(x.property); // looks for x.property, undefined if it doesn't exist
alert(x[property]); // looks for x['test'], alerts hi
So what you actually want is:
alert(data[bsID][0].time);
EDIT:
Not sure what you're doing wrong, but this is working for me on Firebug's console:
var data = {"A5A50000":[{"bsid":"A5A50000","chanCount":17,"time":"2009-05-27 16:36:45","avgInterference":1.711765,"maxInterference":4.97,"avgHandsets":205.1176,"maxHandsets":315,"avgCalls":6.4118,"maxCalls":13,"avgCBA":3868.98059,"maxCBA":7463,"sumSuccessCBA":197318,"sumTimeoutHandoff":133,"sumAttemptHandoff":1028,"sumDeniedHandoff":216,"sumConfirmHandoff":679,"sumHandoffNetwork":61873,"sumJoinNetwork":96888,"sumLeaveNetwork":93754,"sumRcvdKeepalive":98773,"sumTimeoutKeepalive":19748,"sumAttemptUplink":93689,"sumBlockedUplink":62453}]};
var bsID = 'A5A50000';
alert(data[bsID][0].time);

In Javascript, you can use either object or array-style notation to look up an attribute. The following are equivalent:
data.A5A50000
data['A5A50000']
With the second syntax, you can use a variable in place of an object string:
data[bsID][0]

I experienced the same problem with a nested JSON API-response:
[
{
"bj_code": "2019",
"BJ_PERIODE": [
{
"nummer": 1
},
{
"nummer": 2
}
]
}
]
I could evaluate:
pm.expect(pm.response.json()[0].BJ_PERIODE[1].nummer).to.eql(2);
But working with BJ_PERIODE and nummer through a variable didn't work.
Writing it with the bracket method did work, even in this nested JSON, like this:
const periode = "BJ_PERIODE";
const nr = "nummer";
pm.expect(pm.response.json()[0][periode][1][nr]).to.eql(2);