Javascript Push to Array if Condition is Met - javascript

I have the following Foods Object:
var Foods = {
"Fruits": [{
"id": "1",
"Name": "Granny Smith",
"Category": "1"
}, {
"id": "2",
"Name": "Raspberries",
"Category": "1"
}
],
"Potatoes": [{
"id": "3",
"Name": "Maris Piper",
"Category": "2"
}, {
"id": "4",
"Name": "Charlotte",
"Category": "2"
}]
}
What I would like to do is only push the produce that matches an id passed by a link.
Get Foods
This is what I have tried so far:
function getCat (id){
result = [];
for(let item in Foods) {
if(Foods[item].id == id) {
data[item].foreach(v=>result.push("<div class='box'><h2>" +
data[key].Name + "<br></div>"));
}
}
}
display();
function display() {
alert(result);
}
So if a user hits the link (which has an id of 2), the result array should contain "Charlotte" and "Maris Piper" but I am just drawing a blank.
Any help appreciated.
Cheers


Youre quite close, however theres a slight problem:
for(let item in Foods) {
console.log(Foods[item]);
/*
[{
"id": "1",
"Name": "Granny Smith",
"Category": "1"
}, {
"id": "2",
"Name": "Raspberries",
"Category": "1"
}
]
*/
So youre iterating over the categories, which are arrays.
Foods[item].id
is undefined as its an array and not a product. So we need to iterate the array to, e.g.
var result=[];
Object.values(Foods).forEach(function(category){
category.forEach(function(product){
if(product.id===id){
result.push(product);
}
});
});
Run
But if youre doing this quite often, it might be easier to create one product array once:
var products = Object.values(Foods).reduce((arr,cat)=>arr.concat(cat),[]);
So you can simply filter this whenever someone clicks a button:
var result = products.filter(product=>product.id === id);
Run


You're somewhat on the right track, but what's data? Why are you not doing anything with result? And you should be looking at the Category property rather than ID.
This'll work:
function getCat(id) {
let result = [];
for (let item in Foods) {
if (Foods.hasOwnProperty(item)) {
Foods[item].forEach((food) => {
if (food.Category == id) {
result.push(food);
}
});
}
}
console.log(result);
}


First of all result array should be at global scope so that you can access it in another function, And in object you are having categories then each category has some data in array so after iterating over object, you need to iterate the items from array as well to get the value. Check the below code.
var result = [];
function getCat(id){
for(let item in Foods) {
var foodItem = Foods[item];
for(let i=0; i<foodItem.length; i++){
if(foodItem[i].id == id) {
result.push("<div class='box'><h2>" + foodItem[i].Name + "<br></div>"));
}
}
}
}
function display() {
alert(result);
}
display();


Iterator is wrong. You should do it like this:
function getCat(id){
result = [];
for(let item in Foods) {
Foods[item].forEach(function(each){
if(each.id == id) { // you cmpare to the wrong target
// do something
}
});
}
}

Related

splice array base on property value

$scope.myJson = [{
"id": "1",
"name": "banana",
"price": 12,
"qty": 3,
}, {
"id": "2",
"name": "watermelon",
"price": 12.9,
"qty": 4,
}];
for(i = 0; i < $scope.myJson.length; i++) {
if($scope.myJson[i]._id == '2'){
//what to do here?
//then save back to localstorage
}
}
I'm using localstorage so I have to find array and splice it. I don't know how to proceed.

Splice is the worst option in terms of performance.
Yet in your case you would need to do:
$scope.myJson.splice(i,1);
See performance comparison here: https://jsperf.com/splice-vs-filter
I would at least do a filter:
$scope.myJson = $scope.myJson.filter(function(obj) {
return (obj.id !== '2');
}) ;

Just iterate through the array, search for the desired property value and splice the array.
function spliced(array, value) {
var arr = array.slice(0);
array.forEach(function (obj) {
if (obj.hasOwnProperty('id')) {
if (obj['id'] == value ) {
arr.splice(arr.indexOf(obj),1);
}
}
});
return arr;
}
console.log( spliced(arr, 1) )

Removing Duplicate object from array in jquery code not working

This is my array in jquery , which contains duplicate objects/elements :
[{
"name": "hello",
"label": "world"
}, {
"name": "abc",
"label": "xyz"
}, {
"name": "hello",
"label": "world"
}]
I am using the following piece of code to remove duplicate elements but it not working the duplicate elements are not removed.
var result = [];
$.each(subservices, function (i, e) {
if ($.inArray(e, result) == -1)
result.push(e);
});
alert(JSON.stringify(result));

Function $.inArray works fine for simple types (e.g. number or string), but for complex types it does not produce the correct result, because it tries to match by reference. Instead of using inArray in your loop you can search the array using function grep:
var subservices = [{
"name": "hello",
"label": "world"
}, {
"name": "abc",
"label": "xyz"
}, {
"name": "hello",
"label": "world"
}
];
var result = [];
$.each(subservices, function (i, e) {
var matchingItems = $.grep(result, function (item) {
return item.name === e.name && item.label === e.label;
});
if (matchingItems.length === 0){
result.push(e);
}
});
//displays result [{"name":"hello","label":"world"},{"name":"abc","label":"xyz"}]
alert(JSON.stringify(result));
Here is a working jsFiddle

You need to filter array by unique name/value. Here is some pure JS solution:
var data = [{
"name": "hello",
"label": "world"
}, {
"name": "abc",
"label": "xyz"
}, {
"name": "hello",
"label": "world"
}];
var result = data.filter(function(el, i, x) {
return x.some(function(obj, j) {
return obj.name === el.name && (x = j);
}) && i == x;
});
alert(JSON.stringify(result, null, 4));

This is because these two objects are distinct, even though all the attributes inside are the same. You can see this from:
console.log(result[0] === result[2]);
which results in false.
Instead, you need to iterate through your array based on a unique identifier, such as name & label as such:
for(var i = 0, i < results.length; i++) {
if (result[i].name === ... && result[i].label === ...) {
index = i;
break;
}
}
to check if your item is unique.

How apply ko.utils.arrayGetDistinctValues on two dimensional arrays

I have an ko.observableArray with two dimensions, i.e. "id" and "name".
Id will always be distinct, but name can hold the same value.
self.myArray = ko.observableArray( [
{ "id": "1", "name": "Barbara" }, 
{ "id": "2", "name": "Edwin" }, 
{ "id": "3", "name": "Barbara" } 
] );
However I want to filter the array so that my result holds only the first occurrence of "name".
The result I want is:
self. myFilteredArray = [
{ "id": "1", "name": "Barbara" }, 
{ "id": "2", "name": "Edwin" } 
];
I have been trying to figure this out using ko.utils.arrayGetDistinctValues(), but how can I utilize it on solely one chosen dimension?

You could use a computed for this:
viewModel.myFilteredArray = ko.computed(function() {
var rv = [], names = [];
for(var i=0; i<this.myArray().length; i++) {
if(names.indexOf(this.myArray()[i].name) === -1) {
rv.push(this.myArray()[i]);
names.push(this.myArray()[i].name);
}
}
return rv;
}, viewModel);

I can suggest a function, that loops through the array, builds map of property values for each item and checks, whether the current value was already added. Something like this:
function filterByFirstOccurance(arr, prop) {
var propValuesHash = {},
result = [];
for (var i = 0, l = arr.length; i < l; i++) {
var item = arr[i],
propValue = item[prop];
if (item.hasOwnProperty(prop) && !propValuesHash[propValue]) {
propValuesHash[propValue] = true;
result.push(item);
}
}
return result;
};
Fiddle

Get specific object by id from array of objects in AngularJS

I have a JSON file containing some data I d like to access on my AngularJS website. Now what I want is to get only one object from the array. So I d like for example Item with id 1.
The data looks like this:
{ "results": [
{
"id": 1,
"name": "Test"
},
{
"id": 2,
"name": "Beispiel"
},
{
"id": 3,
"name": "Sample"
}
] }
I'd like to load the data with AngularJS $http functionality like this:
$http.get("data/SampleData.json");
which is working. But how can I now get a specific data object (by id) from the array I get from $http.get ?

Using ES6 solution
For those still reading this answer, if you are using ES6 the find method was added in arrays. So assuming the same collection, the solution'd be:
const foo = { "results": [
{
"id": 12,
"name": "Test"
},
{
"id": 2,
"name": "Beispiel"
},
{
"id": 3,
"name": "Sample"
}
] };
foo.results.find(item => item.id === 2)
I'd totally go for this solution now, as is less tied to angular or any other framework. Pure Javascript.
Angular solution (old solution)
I aimed to solve this problem by doing the following:
$filter('filter')(foo.results, {id: 1})[0];
A use case example:
app.controller('FooCtrl', ['$filter', function($filter) {
var foo = { "results": [
{
"id": 12,
"name": "Test"
},
{
"id": 2,
"name": "Beispiel"
},
{
"id": 3,
"name": "Sample"
}
] };
// We filter the array by id, the result is an array
// so we select the element 0
single_object = $filter('filter')(foo.results, function (d) {return d.id === 2;})[0];
// If you want to see the result, just check the log
console.log(single_object);
}]);
Plunker: http://plnkr.co/edit/5E7FYqNNqDuqFBlyDqRh?p=preview

For anyone looking at this old post, this is the easiest way to do it currently. It only requires an AngularJS $filter. Its like Willemoes answer, but shorter and easier to understand.
{
"results": [
{
"id": 1,
"name": "Test"
},
{
"id": 2,
"name": "Beispiel"
},
{
"id": 3,
"name": "Sample"
}
]
}
var object_by_id = $filter('filter')(foo.results, {id: 2 })[0];
// Returns { id: 2, name: "Beispiel" }
WARNING
As #mpgn says, this doesn't work properly. This will catch more results. Example: when you search 3 this will catch 23 too

personally i use underscore for this kind of stuff... so
a = _.find(results,function(rw){ return rw.id == 2 });
then "a" would be the row that you wanted of your array where the id was equal to 2

I just want to add something to Willemoes answer.
The same code written directly inside the HTML will look like this:
{{(FooController.results | filter : {id: 1})[0].name }}
Assuming that "results" is a variable of your FooController and you want to display the "name" property of the filtered item.

You can use ng-repeat and pick data only if data matches what you are looking for using ng-show
for example:
<div ng-repeat="data in res.results" ng-show="data.id==1">
{{data.name}}
</div>

You can just loop over your array:
var doc = { /* your json */ };
function getById(arr, id) {
for (var d = 0, len = arr.length; d < len; d += 1) {
if (arr[d].id === id) {
return arr[d];
}
}
}
var doc_id_2 = getById(doc.results, 2);
If you don't want to write this messy loops, you can consider using underscore.js or Lo-Dash (example in the latter):
var doc_id_2 = _.filter(doc.results, {id: 2})[0]

If you want the list of items like city on the basis of state id then use
var state_Id = 5;
var items = ($filter('filter')(citylist, {stateId: state_Id }));

Unfortunately (unless I'm mistaken), I think you need to iterate over the results object.
for(var i = 0; i < results.length; i += 1){
var result = results[i];
if(result.id === id){
return result;
}
}
At least this way it will break out of the iteration as soon as it finds the correct matching id.

Why complicate the situation? this is simple write some function like this:
function findBySpecField(data, reqField, value, resField) {
var container = data;
for (var i = 0; i < container.length; i++) {
if (container[i][reqField] == value) {
return(container[i][resField]);
}
}
return '';
}
Use Case:
var data=[{
"id": 502100,
"name": "Bərdə filialı"
},
{
"id": 502122
"name": "10 saylı filialı"
},
{
"id": 503176
"name": "5 sayli filialı"
}]
console.log('Result is '+findBySpecField(data,'id','502100','name'));
output:
Result is Bərdə filialı

The only way to do this is to iterate over the array. Obviously if you are sure that the results are ordered by id you can do a binary search

$scope.olkes = [{'id':11, 'name':'---Zəhmət olmasa seçim edin---'},
{'id':15, 'name':'Türkyə'},
{'id':45, 'name':'Azərbaycan'},
{'id':60, 'name':'Rusya'},
{'id':64, 'name':'Gürcüstan'},
{'id':65, 'name':'Qazaxıstan'}];
<span>{{(olkes | filter: {id:45})[0].name}}</span>
output: Azərbaycan

If you can, design your JSON data structure by making use of the array indexes as IDs. You can even "normalize" your JSON arrays as long as you've no problem making use of the array indexes as "primary key" and "foreign key", something like RDBMS. As such, in future, you can even do something like this:
function getParentById(childID) {
var parentObject = parentArray[childArray[childID].parentID];
return parentObject;
}
This is the solution "By Design". For your case, simply:
var nameToFind = results[idToQuery - 1].name;
Of course, if your ID format is something like "XX-0001" of which its array index is 0, then you can either do some string manipulation to map the ID; or else nothing can be done about that except through the iteration approach.

I know I am too late to answer but it's always better to show up rather than not showing up at all :). ES6 way to get it:
$http.get("data/SampleData.json").then(response => {
let id = 'xyz';
let item = response.data.results.find(result => result.id === id);
console.log(item); //your desired item
});

The simple way to get (one) element from array by id:
The find() method returns the value of the first element in the array that satisfies the provided testing function. Otherwise undefined is returned.
function isBigEnough(element) {
return element >= 15;
}
var integers = [12, 5, 8, 130, 160, 44];
integers.find(isBigEnough); // 130 only one element - first
you don't need to use filter() and catch first element xx.filter()[0] like in comments above
The same for objects in array
var foo = {
"results" : [{
"id" : 1,
"name" : "Test"
}, {
"id" : 2,
"name" : "Beispiel"
}, {
"id" : 3,
"name" : "Sample"
}
]};
var secondElement = foo.results.find(function(item){
return item.id == 2;
});
var json = JSON.stringify(secondElement);
console.log(json);
Of course if you have multiple id then use filter() method to get all objects.
Cheers
function isBigEnough(element) {
return element >= 15;
}
var integers = [12, 5, 8, 130, 160, 44];
integers.find(isBigEnough); // 130 only one element - first
var foo = {
"results" : [{
"id" : 1,
"name" : "Test"
}, {
"id" : 2,
"name" : "Beispiel"
}, {
"id" : 3,
"name" : "Sample"
}
]};
var secondElement = foo.results.find(function(item){
return item.id == 2;
});
var json = JSON.stringify(secondElement);
console.log(json);

projectDetailsController.controller('ProjectDetailsCtrl', function ($scope, $routeParams, $http) {
$http.get('data/projects.json').success(function(data) {
$scope.projects = data;
console.log(data);
for(var i = 0; i < data.length; i++) {
$scope.project = data[i];
if($scope.project.name === $routeParams.projectName) {
console.log('project-details',$scope.project);
return $scope.project;
}
}
});
});
Not sure if it's really good, but this was helpful for me..
I needed to use $scope to make it work properly.

use $timeout and run a function to search in "results" array
app.controller("Search", function ($scope, $timeout) {
var foo = { "results": [
{
"id": 12,
"name": "Test"
},
{
"id": 2,
"name": "Beispiel"
},
{
"id": 3,
"name": "Sample"
}
] };
$timeout(function () {
for (var i = 0; i < foo.results.length; i++) {
if (foo.results[i].id=== 2) {
$scope.name = foo.results[i].name;
}
}
}, 10);
});

I would iterate over the results array using an angularjs filter like this:
var foundResultObject = getObjectFromResultsList(results, 1);
function getObjectFromResultsList(results, resultIdToRetrieve) {
return $filter('filter')(results, { id: resultIdToRetrieve }, true)[0];
}

javascript and json

I'm using javascript with a json library and running into a little trouble. Here's my json output:
{
"artist": {
"username": "myname",
"password": "password",
"portfolioName": "My Portfolio",
"birthday": "2010-07-12 17:24:36.104 EDT",
"firstName": "John",
"lastName": "Smith",
"receiveJunkMail": true,
"portfolios": [{
"entry": [{
"string": "Photos",
"utils.Portfolio": {
"name": "Photos",
"pics": [""]
}
},
{
"string": "Paintings",
"utils.Portfolio": {
"name": "Paintings",
"pics": [""]
}
}]
}]
}
}
In javascript I'm trying to access the entries in the map like so:
var portfolios = jsonObject.artist.portfolios.entry;
var portfolioCount = portfolios.length;
for ( var index = 0; index < portfolioCount; index++ )
{
var portfolio = portfolios[index];
txt=document.createTextNode("Portfolio Name: " + portfolio['string'] );
div = document.createElement("p");
div.appendChild ( txt );
console.appendChild(div);
}
but portfolios is "undefined". What's the correct way to do this?

Look at your JSON results. portfolios is a one-element array; portfolios[0] is an object containing a single key, entry, which maps to an array of two objects that have both string and utils.Portfolio keys. Thus, the syntax jsonObject.artist.portfolios.entry will not work. Instead, you want jsonObject.artist.portfolios[0].entry.
If possible, I would suggest changing whatever code generates those JSON results to remove the entry level of indirection entirely, e.g. like so:
{
"artist": {
/* ... */
"portfolios": [
{
"string": "Photos",
"utils.Portfolio": {
"name": "Photos",
"pics": [""]
}
},
{
"string": "Paintings",
"utils.Portfolio": {
"name": "Paintings",
"pics": [""]
}
}
]
}
}
Then you could access it with
var portfolios = jsonObject.artist.portfolios;
for (var i = 0, portfolio; portfolio = portfolios[i]; ++i)
{
// use portfolio variable here.
}

There is an array in your object. I believe you're looking for this:
var portfolios = jsonObject.artist.portfolios[0].entry;

The portfolios property is an array, so you need to use an index to get the first element:
var portfolios = jsonObject.artist.portfolios[0].entry;

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