I am working on a single page app using dynamic routing. I get my bookid from the URL as below
myApp.controller('BookCtrl', function($scope,$routeParams) {
$scope.mybookid=$routeParams.bookurl;
});
Here is my data
var bookdata = {
"records": [
{
"seriesid": "SpectrumSeries",
"name": "White Curse",
"bookid": "WhiteCurse",
"image": "book1",
}
...
]};
In the above controller, how to I filter out an object that has bookid that equals to $scope.mybookid? I know I can do this by ng-repeat and filter but is there a more efficient way?
Use filter in javascript:
var filteredBooks = bookdata.records.filter(function(book){
return book.bookid == $scope.mybookid;
});
The filteredBooks array will contains all the book with your bookId.
Related
I have been trying to parse JSON, which have 3 different set of data where one element have various number of children and sometimes none. I am getting an error when there is no children present or only one present. I declared the JSON as var data.
JSON A
{
"floorplan": [
{
"title": "plan1",
"url": "https://media.plan1.pdf"
},
{
"title": "plan2",
"url": "https://media.plan2.pdf"
}
]
}
JSON B
{"floorplan": []}
JSON C
{
"floorplan": [
{
"title": "plan1",
"url": "https://media.plan1.pdf"
}
]
}
I parsed the JSON like this:
var items = JSON.parse(data);
return {
floorplan1: items.floorplan[0].url;
floorplan2: items.floorplan[1].url;
}
But, it only returned data for the JSON A, for other 2 it gave TypeError: Cannot read property 'url' of undefined.
I modified the code to check if floorplan have at least one child and then parse data.
var items = JSON.parse(data);
var plan = items.floorplan[0];
if(plan){
return {
floorplan1: items.floorplan[0].url;
floorplan2: items.floorplan[1].url;
}
}
The new code returned data for JSON A and B(as empty row), but gave error for C. C have one child still it got the error.
I also tried this code, still got the error for JSON C.
var items = JSON.parse(data);
var plan = items.floorplan[0];
var plan1;
var plan2;
if(plan){
plan1 = items.floorplan[0].url;
plan2 = items.floorplan[1].url;
}
return{
floorplan1 : plan1 ? plan1 : null;
floorplan2 : plan2 ? plan2 : null;
}
Is there any method I can try to get data returned for all 3 types of JSON?
let data = `
[{"floorplan": [{
"title": "plan1",
"url": "https://media.plan1.pdf"
}, {
"title": "plan2",
"url": "https://media.plan2.pdf"
}]},
{"floorplan": []},
{"floorplan": [{
"title": "plan1",
"url": "https://media.plan1.pdf"
}]}]`;
let json = JSON.parse(data);
//console.log(json);
json.forEach(items=>{
//console.log(items);
let o = {
floorplan1: items.floorplan.length > 0 ? items.floorplan[0].url : '',
floorplan2: items.floorplan.length > 1 ? items.floorplan[1].url : ''
};
console.log(o);
o = {
floorplan1: (items.floorplan[0] || {'url':''}).url,
floorplan2: (items.floorplan[1] || {'url':''}).url
};
console.log(o);
o = {
floorplan1: items.floorplan[0]?.url,
floorplan2: items.floorplan[1]?.url
};
console.log(o);
const {floorplan: [one = {url:''}, two = {url:''}]} = items;
o = {
floorplan1: one.url,
floorplan2: two.url
};
console.log(o);
});
Sure. A few ways, and more than I have here. I have put all the raw data into one string, parsed it into json and then iterated through that. In each loop my variable items will correspond to one of the json variables you created and referenced in your question as items.
In the first example, I check to make sure that items.floorplan has at least enough elements to contain the url I'm trying to reference, then use the ternary operator ? to output that URL if it exists or an empty string if it doesn't.
In the second example, I use the || (OR) operator to return the first object that evaluates to true. If items.floorplan[x] exists, then it will be that node, and if it doesn't I provide a default object with an empty url property on the right hand side, and then just use the url from the resulting object.
In the third, I use the optional chaining operator that was introduced in 2020. This method will return undefined if the url doesn't exist.
In the fourth example, I use destructuring to pull values out of the items variable, and make sure that there is a default value for url in case the items variable doesn't have a corresponding value.
But there are many more ways to go about it. These are just a few, and you can't necessarily say which approach is better. It's dependent on your intent and environment. With the exception of optional chaining (which shows undefined if the property doesn't exist), you can see these produce the same results.
DOCS for optional chaining: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Optional_chaining
DOCS for destructuring: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Destructuring_assignment
An article on destructuring: https://javascript.info/destructuring-assignment
{
"vitals": {
"title": "Vitals IR",
"name": "vitalsIr",
"formid":"5ed5f7ca158a91827891cab2"
},
"anthropometry": {
"title": "Anthropometry IR",
"name": "anthropometryIr",
"formid":"5ed621ac158a91228191cafd"
}}
How to get the root key name vitals , anthropometry based on formid value
for example if formid value is "5ed621ac158a91228191cafd"
I need output as anthropometry need to achieve this in angular javascript
To loop through a json object using JavaScript, you can preform a for on the keys. E.g for (jsonPropertyName in json) { ... }. You can then query the formId.
For example:
function ProvideRootKey(formId) {
var results;
for (jsonPropertyName in json) {
if (json[jsonPropertyName]['formid'] === formId) {
results = jsonPropertyName
}
}
return results
}
var json = JSON.parse('{ "vitals":{ "title":"Vitals IR", "name":"vitalsIr","formid":"5ed5f7ca158a91827891cab2"}, "anthropometry":{ "title":"Anthropometry IR", "name":"anthropometryIr", "formid":"5ed621ac158a91228191cafd"}}');
console.log(ProvideRootKey('5ed621ac158a91228191cafd'))
Output (in console log):
"anthropometry"
See working example: https://jsfiddle.net/vgo81stm/1/
Say I have a JSON request payload like
{
"workflow": {
"approvalStore": {
"sessionInfo": {
"user": "baduser"
},
"guardType": "Transaction"
}
}
}
I get the value of user via
def user = req.get("workflow").get("approvalStore").get("sessionInfo").get("user")
Now, I get a RestResponse approvalList which I store as list and return to caller as return approvalList.json as JSON. All well so far.
Suppose the response (approvalList.json) looks like below JSONArray -
[
{
"objId": "abc2",
"maker": "baduser"
},
{
"objId": "abc1",
"maker": "baduser"
},
{
"objId": "abc4",
"maker": "gooduser"
}
]
Question : How may I filter the approvalList.json so that it doesn't contain entries (objects) that have "maker": "baduser" ? The value passed to maker should essentially be the user variable I got earlier.
Ideal required output -
It's not entirely clear if you always want a single object returned or a list of objects but using collect is going to be the key here:
// given this list
List approvalList = [
[objId: "abc2", maker: "baduser"],
[objId: "abc1", maker: "baduser"],
[objId: "abc4", maker: "gooduser"]
]
// you mentioned you wanted to match a specific user
String user = "baduser"
List filteredList = approvalList.findAll{ it.maker != user}
// wasn't sure if you wanted a single object or a list...
if (filteredList.size() == 1) {
return filteredList[0] as JSON
} else {
return filteredList as JSON
}
Pretty simple. First parse the JSON into an object, then walk through and test.
JSONObject json = JSON.parse(text)
json.each(){ it ->
it.each(){ k,v ->
if(v=='baduser'){
// throw exception or something
}
}
}
I use a WebSocket to communicate to a server in my Flutter app. Let's say I receive a JSON object trough the WebSocket :
{
"action": "getProduct",
"cbackid": 1521474231306,
"datas": {
"product": {
"Actif": 1,
"AfficheQte": 0,
"Article": "6"
},
"result": "success"
},
"deviceID": "4340a8fdc126bb59"
}
I have no idea what the content of datas will be until I read the action, and even then, it's not guaranteed to be the same every time. One example of a changing action/datas is when the product doesn't exist.
I can parse it in a Map<String, Object>, but then, how do I access what's inside the Object?
What's the correct way to read this data?
Not sure what the question is about, but you can check the type of the values and then continue accordingly
if(json['action'] == 'getProduct') {
var datas = json['datas'];
if(datas is List) {
var items = datas as List;
for(var item in items) {
print('list item: $item');
}
} else if (datas is Map) {
var items = datas as Map;
for(var key in items.keys) {
print('map item: $key, ${items[key]}');
}
} else if(datas is String) {
print('datas: $datas');
} // ... similar for all other possible types like `int`, `double`, `bool`, ...
}
You also can make that recursive to check list or map values if they are String, ...
I'm retrieving the following structure from Firebase:
"bills" : {
"1" : { // the customer id
"orders" : {
"-KVMs10xKfNdh_vLLj_k" : [ { // auto generated
"products" : [ {
"amount" : 3,
"name" : "Cappuccino",
"price" : 2.6
} ],
"time" : "00:15:14"
} ]
}
}
}
I'm looking for a way to process this with Aurelia. I've written a value converter that allows my repeat.for to loop the object keys of orders, sending each order to an order-details component. The problem is, this doesn't pass the key, which I need for deleting a certain order ("-KVMs10xKfNdh_vLLj_k")
Should I loop over each order and add the key as an attribute myself?
Is there a better/faster way?
This answer might be a little late (sorry OP), but for anyone else looking for a solution you can convert the snapshot to an array that you can iterate in your Aurelia views using a repeat.for, for example.
This is a function that I use in all of my Aurelia + Firebase applications:
export const snapshotToArray = (snapshot) => {
const returnArr = [];
snapshot.forEach((childSnapshot) => {
const item = childSnapshot.val();
item.uid = childSnapshot.key;
returnArr.push(item);
});
return returnArr;
};
You would use it like this:
firebase.database().ref(`/bills`)
.once('value')
.then((snapshot) => {
const arr = snapshotToArray(snapshot);
});