I have the following JSON Object which I want to copy/clone.
While cloning I want only a few specific keys, say id, measurement_tag_id and unit.
Following is my JSON object:
{
"id": 246,
"measurement_profile_id": 52,
"measurement_tag_id": 339,
"unit": "in",
"value": 5,
"measurement_tag": {
"id": 339,
}
...
...
...
...many more keys...
}
How can I achieve this in coffeescript, using only one liners?
This is very simple to do with a for loop:
new_object = {}
new_object[key] = old_object[key] for key in ["id", "measurement_tag_id", "unit"]
Related
Using the below json as an example I want to write a js code that will only return the objects that contain specific name-value pairs:
Use case 1: return only the json objects containing the name-value pair "currency": "RON"
Use case 2 for nested pairs: return only the json objects containing the name-value pair "product_id": "1084929"
I want this done in plain js, not jquery.
Why would this be helpful for me? I sometimes have to validate large json files and it would help to "contract" the json to certain objects that interest me based on a specific use case.
{
"results": [
{
"currency": "RUB",
"status": "approved",
"order_id": "Y3411851",
"click_country_code": "RU",
"positions": [
{
"product_id": "1084929",
"amount": "2290.00"
}
],
"action_date": "2019-03-30 00:42:23",
"processed": 1,
"action_type": "sale",
"action": "Оплаченный заказ"
},
{
"currency": "RON",
"status": "declined",
"order_id": "Y3415290",
"click_country_code": "RO",
"positions": [
{
"product_id": "1052297",
"amount": "4390.00"
}
]
}
]
}
Try this:
Assuming that your 'results' array is inside an object called 'obj', first do:
let results = obj.results;
then,
case 1:
results.filter(obj=>obj.currency === "RON")
case 2:
results.filter(
obj =>
Array.isArray(obj.positions) &&
obj.positions.some(
position => position && position.product_id === "1084929"
)
);
I have an array of objects that looks like this:
[
{
"id": 123,
"timeStamp": "\"2019-07-08T20:36:41.580Z\"",
"data": [1, 2, 3]
},
{
"id": 234,
"timeStamp": "\"2019-07-08T20:37:12.472Z\"",
"data": ["Apples", "Oranges"]
}
]
I want to update the value of a particular property of an object within the array but also want to make sure that I return the result in a new array.
How do I do this without running through some type of a loop e.g. for loop?
Say, I want to update the data property of the second object and add Bananas to it.
If you want the result to be a new array, you'll first have to clone the array. This can be more complicated than you might imagine (depending on how deeply you wish to clone things). One way is to use JSON stringify...
Bear in mind that the JSON trick is effectively doing a loop behind the scenes. Inevitable if you want to copy the array, really.
To find the object by ID use Array.find()
let original = [
{
"id": 123,
"timeStamp": "\"2019-07-08T20:36:41.580Z\"",
"data": [1, 2, 3]
},
{
"id": 234,
"timeStamp": "\"2019-07-08T20:37:12.472Z\"",
"data": ["Apples", "Oranges"]
}
]
let copy = JSON.parse(JSON.stringify(original));
copy.find(obj => obj.id === 234).data.push("Bananas");
console.log(copy);
Something like this would do the trick:
let arr = [
{
"id": 123,
"timeStamp": "\"2019-07-08T20:36:41.580Z\"",
"data": [1, 2, 3]
},
{
"id": 234,
"timeStamp": "\"2019-07-08T20:37:12.472Z\"",
"data": ["Apples", "Oranges"]
}
]
arr[1]['data'] = [...arr[1]['data'], 'Bananas']
console.log(arr)
For your example: you can do something like this: say your array of object is saved in test variable
test[1].data.push("Bananas")
I recently got interested on using the spread operator syntax, so I tried some examples, I have this example of array:
var entities = [
{
"id": 1,
"age": 33,
"hobby": "games"
},
{
"id": 2,
"age": 28,
"hobby": "chess"
},
{
"id": 3,
"age": 21,
"hobby": "comics"
},
{
"age": 23,
"hobby": "games"
}
]
Then, to update all hobbies at "once" I do the following:
entities.forEach(function(entity, index) {
this[index] = {...entity, hobby: "Some String to update all hobbies"};
}, entities);
console.log(entities)
Which works but I was wondering if there's a more efficient or shorter way to achieve it while using the spread operator. Any suggestions?
EDIT:
forEach is not necessary for me, or even do it in that way, I was curious on whether the spread syntax could be used (or not) to update nested values
The spread operator doesn't really help when you're updating the list, like you do in your example. It's easier to just update the property of each object:
var entities = [ { "id": 1, "age": 33, "hobby": "games" }, { "id": 2, "age": 28, "hobby": "chess" }, { "id": 3, "age": 21, "hobby": "comics" }, { "age": 23, "hobby": "games" } ]
entities.forEach(entity => {
entity.hobby = "Some String to update all hobbies";
});
console.log(entities)
The spread operator is useful if you want to create copies of objects, like you might want to do in a .map:
var entities = [ { "id": 1, "age": 33, "hobby": "games" }, { "id": 2, "age": 28, "hobby": "chess" }, { "id": 3, "age": 21, "hobby": "comics" }, { "age": 23, "hobby": "games" } ]
const newEntities = entities.map(entity =>
({...entity, hobby: "Some String to update all hobbies"})
);
console.log(newEntities)
The spread operator will iterate over all keys in the object to copy them and their values into the new object. If you want more efficiency, don't use the spread operator. Just assign directly to each object as you iterate over the list:
entity.hobby = "Some String to update all hobbies"
Note that this modifies the object in the existing array. So you don't need to assign this[index]. Alternatively, you can use map() instead of foreach() to return a new array that is created from the existing array.
Not sure if spread operator is really needed for what you are doing?
You can also look into this link for some interesting usage of the spread, Array.from and rest operator.
More into just spread operator here.
If you are looking for a fancier/smaller way to write this, here's two, one that uses uses .map and spread to return a copy of entities, and another that uses .forEach and updates the same array entities:
const COMMON_HOBBY = 'Coding';
let entities = [{
"id": 1,
"age": 33,
"hobby": "games"
},
{
"id": 2,
"age": 28,
"hobby": "chess"
}];
// To assign to new array (copy)
let output = entities.map((entity) => ({...entity, hobby: COMMON_HOBBY }));
console.log(output);
// Mutate /edit same array entities
entities.forEach((entity) => entity.hobby = COMMON_HOBBY );
console.log(entities);
when my ajax call completes an array of json is returned
for my angular data binding to work perfectly, i need to merge all values in to a single JSON file. I have tried $.extend(), it's giving following output
Need a solution for this
for example if my response looks like this:
[0:"{'test':'test'}", 1:"{'test':'test'}", 2:"{'test':'test'}",3: "{'test':'test'}"];
the output i need is :
{ test':'test', 'test':'test', 'test':'test', 'test':'test' }
Edit:
The final value will be associated to the ng-model automatically.
desired output example:
{
"unique_id": 172,
"portfolio": "DIGITAL",
"bus_unit": "dummy",
"project_phase": "",
"test_phase": "SIT",
"project": "Google",
"golivedate": "03/09/2016",
"performance": "Green",
"summary": "jgnbfklgnflknflk",
"last_updated": "",
"risks_issues": "gfmngfnfglkj",
"project_start": "03/16/2016",
"batchLast_run": "",
"custom_project": "1",
"test_execution_id": 5456,
"unique_id": 172,
"test_execution_id": 5456,
"pass": 8,
"fail": 8,
"blocked": 8,
"in_progress": 8,
"no_run": 8,
"not_available": 0,
"total": 8
}
From what I understand you are trying to convert array of Json data into one singel json data. So you have array of values but you would want all of them in one variable. Try this
var testData = ["{'test':'test'}", "{'test':'test'}", "{'test':'test'}", "{'test':'test'}"];
var finalData ="";
$.each(testData,function(index,value){
finalData += value +',';
});
finalData = finalData.replace(/\},\{/g,',').slice(0, -1);
document.write(finalData);
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
Map just applies the function to every element in the array.
var arrayOfJSON = ...
var arrayOfObjects = arrayOfJSON.map(function (jsonString){
return JSON.parse(jsonString)
})
var jsonStringWithAllObjects = JSON.stringify(arrayOfObjects)
If you use underscore.js then can easily
like:
var list = [{"test1": "test1"}, {"test2": "test2"}, {"test3": "test3"}];
var newList = _.extend.apply(null,[{}].concat(list));
then output will be
{ test1: "test1", test2: "test2", test3: "test3" }
Iterate over the array, convert every value to a JSON object, concatenate and then convert to a string back.
If you need fo this more times, you probably should make this a function.
Can I create an object dynamically from JSON?
This is one of some in array:
values: [{
"$type": "Entrance, DataModel",
"EntranceDeviceData": {
"$type": "DeviceData, DataModel",
"Watchdog": 0,
"Inputs": {
"$type": "Int16[], mscorlib",
"$values": [0, 0]
},
"Outputs": {
"$type": "Int16[], mscorlib",
"$values": [0, 0]
},
"Faults": {
"$type": "Int16[], mscorlib",
"$values": [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
},
"StandingCommand": 0
},
"Vehicle": null,
"NextStates": {
"$type": "System.Collections.Generic.List`1[[System.String, mscorlib]], mscorlib",
"$values": ["CarApproachingBarrier"]
},
"Repository": {
"$type": "System.Collections.Generic.Dictionary`2[[System.String, mscorlib],[System.Object, mscorlib]], mscorlib"
},
"Direction": 0,
"Name": "Entrance",
"Position": "0,0,0,0",
}, {...another object...
}, {...another one...
}
]
This both JSON objects are different. Can I create an object (for every other JSON object) without knowing in advance it's properties? How can I do it?
(I heard something that it possible, but maybe I didn't understand well the person who said that).
What you gave as examples of JSON in your original code above is Javascript's way of defining literal objects. json1 and json2 already ARE javascript objects, no need to create them.
// original code from question
var json1 = {
"mysex": "female",
"yoursex": "male",
"location": {
"lat": "48",
"lng": "1"
},
"description": "descr2",
"owner": "zBYnfuu8DXEwMttwZ",
"nickname": "user",
"_id": "1"
};
As nnnnnn pointed out below JSON is most commonly used to refer to a STRING containing code formatted as above, that would be:
var json1_as_string = '{
"mysex": "female",
"yoursex": "male",
"location": {
"lat": "48",
"lng": "1"
},
"description": "descr2",
"owner": "zBYnfuu8DXEwMttwZ",
"nickname": "user",
"_id": "1"
}';
To get from such a String to an actual Javascript Object you would need to parse it:
var json1 = JSON.parse(json1_as_string);
the opposite direction (Javascript Object to String) is achieved by stringify:
var json1_as_string = JSON.stringify(json1);
see https://developer.mozilla.org/en-US/docs/Using_native_JSON
p.s.
It does seem strange that these two very different objects have the same "_id".
You've changed the question completely, and I'm trying to understand what you are asking.
This both JSON objects are different. Can I create an object (for
every other JSON object) without knowing in advance it's properties?
How can I do it?
Yes, in Javascript you can create objects without knowing their properties in advance. Javascript is not strongly typed, and it has no classes. So there's absolutely no problem
with having objects with different properties.