adding variable values in json file using push function - javascript

I have a json file and two variables, i want to store the variables values in the json file using push function in json. my code is
var x=xmen;
var z=xmen website
var jsonObj = {
"items":
[
{
"title":"some title",
"url":"some url"
}
]
};
I want my resulting json file to be
var jsonObj = {
"items":
[
{
"title":"some title",
"url":"some url"
}
{
"title":"xmen",
"url":"xmen website"
}
]
};
I dont want to use arrays just while pushing the value using
jsonObj.items.push
i want to call the variable and assign like example
jsonObj.items.push({"title":+x+,"url":+url+}); //just to explain, its not the original function.

I don't think push is your problem. It's your object syntax that's messed up.
Instead of
{"title":+x+,"url":+url+}
Try this instead:
// Assuming that "x" and "url" are valid variables
{"title":x,"url":url}
Here's a quick demo of everything working: http://jsbin.com/zicofoye/1/edit
jsonObj.items.push({
"title":"avengers",
"url":"avengers website"
});

Related

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)

Edit json in js/node.js?

I am working on an nodejs app which reads data from a json file. Now I want to edit this json file in js (write to it). How do I do this ?
Here is my js code: `
var fs = require("fs")
//function for file input
function getFile(filename) {
var data = fs.readFileSync(filename,"ascii")
return data }
//parsing json
var jsonString = [getFile("File.json")]
var jsonObj = JSON.parse(jsonString)`
Modify the jsonObj as you want, create a new object or whatever, then write the file:
fs.writeFileSync("File.json", jsonData);
This will overwrite the file if it exists, so that way you edit the file.
You can load a json file by requiring it.
var contents = require('/path/to/file.json');
Iterate contents just like a regular object.
A JSON object, when parsed is, like any other JS object. Use object dot notation to access any data you want.
For example a value:
console.log(isonObi.something.value)
For example a value in an array:
console.log(isonObi.something[0].value)
From eyp
Modify the jsonObj as you want, create a new object or whatever, then write the file:
fs.writeFileSync("File.json", jsonData);
This will overwrite the file if it exists, so that way you edit the file.
With nodeJS, you can require a JSON file.
Supposing you get this JSON file :
//test.json
[
{
"name": "toto",
"code": "4"
},
{
"name": "test",
"code": "5"
}
];
Then, you can require this file and perform some modification :
var json = require('./test.json');
json.forEach(function(elm){
elm.name = 'test';
});

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.

how to create json object in angular js

this.addToCart = function(id,name,category,price) {
alert(id+"name"+name);
var eachProduct = [
{
"name": name,
"id": id,
"category":category,
"price":price
}
];
alert(eachProduct.name);//I am getting undefine
addedProductsList.push(eachProduct);
sessionStorage.setItem("addedProductsList", addedProductsList);
return "success";
};
How to pass the function parameters to each product?
As Abdul has pointed out you have a JSON array and you want a JSON object, there you need
var eachProduct =
{
"name": name,
"id": id,
"category":category,
"price":price
};
Now alert(eachProduct.name); will return name. And I assume by "How to pass the function parameters to the each product" you mean add an attribute to your JSON object. To do this you you would have
eachProduct["someAttribute"]='"value":someValue';
You have declared eachProduct as an array, you need to use eachProduct[0].name instead.
You can use forEach to iterate through the array. Please find the jsFiddle working on your example.
Snippet of code:
eachProduct.forEach(function(obj){
alert(obj.name);
});

How to extract data from this JSON string?

I'm new to JSON and Jquery, and I can't find how to extract the values of ProjectCode from this JSON string.
[
{
"ProjectID": 3,
"CLustomerCode": "XYZ001",
"ProjectCode": "YZPROJ1",
"Description": "Project1",
"IssueManager": "iant",
"NotificationToggle": false,
"ProjectStatus": null,
"Added": "/Date(1400701295853}/",
"Added By": "iant",
"Changed": "/Date(1400701295853)/",
"Changed By": "iant"
},
{
"ProjectID": 4,
"CustomerCode": "XYZ001",
"ProjectCode": "XYXPROJ2",
"Description": "Projecton:Project2",
"IssweManager": "iant",
"NotificationToggle": false,
"Projectstatus": null,
"Added": "lDate(1400701317980)/",
"AddedBy": "iant",
"Changed": "/Date(1400701317980)/",
"Changed By": "iant"
}
]
The string above is from a variable called data that is the return value from stringify. I expected to be able to do something like
string proj = data[i].ProjectCode;
but intellisense doesn't include any of the properties.
I know very little about JSON - any help appreciated.
Thanks for reading.
Use parseJSON:
var obj = jQuery.parseJSON("{ 'name': 'Radiator' }");
alert(obj.name);
You need to loop through each object returned in the response and get the ProjectCode property inside each one. Assuming the data variable is your JSON this should work:
$.each(data, function(i, obj) {
console.log(obj.ProjectCode);
});
Use JSON.parse():
var a; // Your JSON string
var b = JSON.parse(a); //Your new JSON object
//You can access Project code, use index i in b[i].ProjectCode in a loop
var projectCode = b[0].ProjectCode;
You should post the raw code so its easier to visualize this stuff. Since what you are looking for is the list of ProjectCodes (in this case - ["XYZPROJ1", "XYZPROJ2"]).
It seems like what we have is an array or list ([...]) of projects. Where each project has a ProjectID, CustomerCode, ProjectCode, Description and so on...
So lets assume data points at this JSON blob. Here is how you would go about accessing the ProjectCode:
// Access the "i"th project code
var p_i_code = data[i].ProjectCode;
// How many projects?
var num_projects = data.length; // since data is a list of projects
// Want the list of project codes back? (I use underscore.js)
var project_codes = _.map(data, function(project) {
return project.ProjectCode;
});

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