In a AngularJS environment I've got two JSON objects like the following:
var rowData = {
fields: {
Id: 1234,
Code: xyz
}
};
var access = {
0: "fields['Id']"
}
now I want to access the value of rowData.fields['Id'] generic by evaluating the value of access[0].
I tried:
var result = rowData.access[0]
which of course does not work. Problem seems to be that the value of access[0] is a string.
How do I convert this to being usable in this given scenario?
Since you want this in the context of Angular, you can utilize the $parse service (ref):
var getter = $parse(access[0]);
var result = getter(rowData);
Related
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;
i have:
var optiontable = {1: 'attack', 2: 'defence', 3: 'intelligence'};
var option = 1;
var minion = minions[thisminion]; // get correct, works.
console.log(optiontable[option]); // would output "attack"
var nameoption = optiontable[option];
var increasement = 8;
how would i do to get the minion.attack based on:
thisminion.nameoption // this wont work when it should display the result of thisminion.attack
and get the nameoption to use in:
minions.update({
_id: thisminion._id,
userid: playerid
}, {$inc: {nameoption: increasement}})
Hard to tell without looking at the rest of the code, but looks like you just need to change
thisminion.nameoption
to
thisminion[nameoption]
Since your original line is trying to access thisminion's property called 'nameoption'. Using square brackets would access the property named the same as the value of nameoption.
As for the mongo part: since you can't use a variable as left-hand value, you need to do a little bit of extra work:
var updateObj = {};
updateObj[nameoption] = increasement;
then you can do this:
minions.update({
_id: thisminion._id,
userid: playerid
}, {$inc: updateObj})
Similar questions:
How to set mongo field from variable
Using variables in MongoDB update statement
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)
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.
I have a json arry
var students = {"apResults":[{"offid":"267","item_name":"","offer_name":"fsdfsf","stlongitude":"77.5945627","stlatitude":"12.9715987"},
{"offid":"265","item_name":"","offer_name":"vess offer shops","stlongitude":"","stlatitude":""},
{"offid":"264","item_name":"","offer_name":"vess ofer shop","stlongitude":"","stlatitude":""},
{"offid":"263","item_name":"","offer_name":"ofer frm vess","stlongitude":"77.5943760","stlatitude":"12.9716060"},
{"offid":"262","item_name":"","offer_name":"offer hungamma","stlongitude":"77.5943760","stlatitude":"12.9716060"},
{"offid":"261","item_name":"","offer_name":"offer hungamma","stlongitude":"77.5943760","stlatitude":"12.9716060"},
{"offid":"260","item_name":"","offer_name":"offer1","stlongitude":"77.5943760","stlatitude":"12.9716060"},
{"offid":"259","item_name":"","offer_name":"offer","stlongitude":"77.5943760","stlatitude":"12.9716060"}]}
How i can parse this json arry using json.parse. I have tried this code
for(i=0;i<students.apResults.length;i++)
{
var contact = JSON.parse(students.apResults);
var offid = contact.offid;
alert(offid)
}
But its giving an error JSON.parse: unexpected character.Edited my question
That's not a json string, that's a regular javascript variable:
for(i=0;i<students.Maths.length;i++)
{
var contact = students.Maths[i];
var fullname = contact.Name;
alert(fullname)
}
for(i=0;i<students.apResults.length;i++)
{
var contact = JSON.parse(students.apResults[i].offid);
alert(contact)
}
JSON parses strings, not objects/arrays.
why need parsing when you can access it like students.Maths[i].Name
students is not a JSON array, it's an actual array. You don't have to parse because it's not a string. So you can access directly to the data you need:
for(i=0;i<students.Maths.length;i++) {
var contact = students.Maths[i];
var fullname = contact.Name;
alert(fullname)
}
You can't parse students because is not a JSON. It's simple object.
However this will work:
var students = JSON.stringify(students); // if you want to send data
students = JSON.parse(students); // after receiving make a object from it
//use like any object
for(i=0;i<students.Maths.length;i++)
{
var contact = students.Maths[i];
var fullname = contact.Name;
alert(fullname)
}
Of course it doesn't make sense to write it that way unless you send students data to other site or program.
Edit:
You don't need JSON in this code at all. But if you want to test JSON.parse() do it this way:
var students = { ... } // your data
var students = JSON.stringify(students); // students is `object`, make it `string`
students = JSON.parse(students); // now you can parse it, `students` is object again
for(i=0;i<students.apResults.length;i++) {
var contact = students.apResults; // no JSON
var offid = contact.offid;
alert(offid)
}
That should work.
What you have is a javascript object. So, you won't need the JSON.parse
for(i=0;i<students.Maths.length;i++)
{
var contact = students.Maths[i]);
var fullname = contact.Name;
alert(fullname)
}
this should be ok
The idea of JSON is for the exchange of objects represented as a structured string (in a nutshell). What you've got there is simply an object. It's unnecessary (and impossible) to parse and object that isn't JSON into a javascript object; what you have is the outcome of what you would expect from a parsed JSON string.