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Javascript how do i dynamically find keys in my array? [duplicate]

This question already has answers here:
Getting key of each object inside array of objects into an array: Javascript
(4 answers)
Closed last year.
I'm trying to find all the keys that are in my array to figure out if some keys already exist in there. Tho when I try to put in the keys seperate like this:
console.log(this.UrlArray.find(({color_ids}) => color_ids));
It works, but if I try doing it with the variable with the actual keys in it:
console.log(this.UrlArray.find(({prefixEqual}) => prefixEqual));
It doesn't work. The values that belong to the keys aren't important, but I stil can't figure out how to do it.
Array example:
(3) [{…}, {…}, {…}]
0:
bd_shoe_size_ids: Array(2)
0: "6601"
1: "6598"
length: 2
[[Prototype]]: Array(0)
[[Prototype]]: Object
1:
color_ids: Array(2)
0: "6056"
1: "6044"
length: 2
[[Prototype]]: Array(0)
[[Prototype]]: Object
2:
manufacturer_ids: Array(2)
0: "5875"
1: "5866"
length: 2
[[Prototype]]: Array(0)
[[Prototype]]: Object
length: 3
[[Prototype]]: Array(0)
I asked something like this before, but I got linkes to answers that had nothing to do with what I'm trying to do and it closed.
As desired outputs I just wanna see bd_shoe_size_ids, color_ids and manufacturer_ids when I console log it.

const data = [
{ bd_shoe_size_ids: [1, 2] },
{ color_ids: [3, 4] },
{ manufacturer_ids: [5, 6] },
];
const output = data.map(Object.keys).flat();
console.log(output);

Angular -> Parsing JSON data into Chart.js bar chart

I have a problem. I have a list of data that I output grouped. Now I want to output the values e.g. erzeugenGes to a barchart. Chart modules itself works. Fail only at the grouped data for evaluation.
Enclosed my code and list
1,2,3,4,5,6,7,8,9,10,11,12 are the Month for the ChartLabels
1.
1: [{…}]
2: [{…}]
3: [{…}]
4: [{…}]
5: [{…}]
6: [{…}]
7: [{…}]
8: [{…}]
9: Array(1)
0: {jahr: 2020, monat: 9, erzeugungGes: 901.04, verbrauchGes: 952.22, eigenverbrauch: 515.24, …}
length: 1
__proto__: Array(0)
10: Array(2)
0:
bezogen: 252.18
eigenverbrauch: 201.62
eingespeist: 140.94
erzeugungGes: 342.53
jahr: 2019
monat: 10
verbrauchGes: 453.75
__proto__: Object
1:
bezogen: 232.07
eigenverbrauch: 174.13
eingespeist: 102.37
erzeugungGes: 276.48
jahr: 2020
monat: 10
verbrauchGes: 406.19
__proto__: Object
length: 2
__proto__: Array(0)
11: Array(1)
0: {jahr: 2019, monat: 11, erzeugungGes: 291.87, verbrauchGes: 761.16, eigenverbrauch: 238.38, …}
length: 1
__proto__: Array(0)
12: [{…}]
/// and Data
getData() {
this.ds.getAuswertungJahr().subscribe(res => {
this.daten = res;
this.data = this.daten.reduce((r, a) => { console.log("a", a); console.log('r', r); r[a.monat] = [...r[a.monat] || [], a]; return r; }, {}); console.log("group", this.data);
this.barChartData[0].data = [];
for (let i = 0; i < this.data.lenght; i++) {
this.barChartData[0].data.push(this.data[i]);
}
})
}
Thanks

Delete from array of object [duplicate]

This question already has answers here:
How can I remove a specific item from an array in JavaScript?
(142 answers)
Closed 4 years ago.
I have an array of objects like this. The result is shown by console.log()
(5) [{…}, {…}, {…}, {…}, {…}]
0:
name:"SOMEVALUE"
partyDetails"SOMEVALUE"
__proto__:Object
1:
name: "SOMEVALUE"
partyDetails: "SOMEVALUE"
__proto__:Object
2:
name:"SOMEVALUE"
partyDetails: "SOMEVALUE"
__proto__: Object
3:
name:"SOMEVALUE"
partyDetails:"SOMEVALUE"
__proto__: Object
4:
name:"SOMEVALUE"
partyDetails: "SOMEVALUE"
__proto__:Object
length:5
__proto__:Array(0)
After deleting from the object by this command,
delete $scope.excelInfo.columnDefs[3];
delete $scope.excelInfo.columnDefs[4];
I get this on console.log
(5) [{…}, {…}, {…}, empty × 2]
0:
name:"SOMEVALUE"
partyDetails:"SOMEVALUE"
__proto__:Object
1:
name:"SOMEVALUE"
partyDetails:"SOMEVALUE"
__proto__:Object
2:
name:"SOMEVALUE"
partyDetails:"SOMEVALUE"
__proto__:Object
length:5
__proto__:Array(0)
How you see there are empty × 2 in the last array of objects, after delete.
What should I do to remove this 2 empty rows?
This 2 empty row make my data wrong in the view.
Is there any good solution?
I do not want to check if data equal to null.
Thanks a lot

You can use splice() to remove last two object without setting undefined as it does when you use delete
var arr = [
{
name:"SOMEVALUE1"
},
{
name:"SOMEVALUE2"
},
{
name:"SOMEVALUE3"
},
{
name:"SOMEVALUE4"
},
{
name:"SOMEVALUE5"
}
];
arr.splice(3,2)
console.log(arr);
Or using delete you need to also filter the defined objects only,
var arr = [
{
name:"SOMEVALUE1"
},
{
name:"SOMEVALUE2"
},
{
name:"SOMEVALUE3"
},
{
name:"SOMEVALUE4"
},
{
name:"SOMEVALUE5"
}
];
delete arr[3];
delete arr[4];
var res = arr.filter(item => item);
console.log(res);

Use Array.splice
$scope.excelInfo.columnDefs.splice(3,2)
e.g.
var arr = [1,2,3,4,5];
arr.splice(3,2);
console.log(arr);

Array.prototype.splice() the array instead of using delete.
$scope.excelInfo.columnDefs.splice(3, 2);
// ^ ^
// | |
// | Number of elements to remove
// Index at which to start removing
splice() modifies the array in place, so there is not need to reassign it.

how to transform object with list of properties to array when Array.prototype.slice.call does not work?

This is working for list:
> Array.prototype.slice.call([1,2,3])
> [1, 2, 3]
How to create list from this type of data {1: "1", 2: "2", 3: "3"} ? Are there other methods than iterating object with for ?
the Array.prototype.slice.call() is not working here and gives []
This came from data = Object {0: Object, 1: Object, 2: Object, total : '29'} and then i delete data['total'] and need to access to slice, pop and other methods of Array

You could use the keys and map the values.
var o = {1: "1", 2: "2", 3: "3"},
a = Object.keys(o).map(function (k) {
return o[k];
});
console.log(a);
console.log(Array.prototype.slice.call({1: "1", 2: "2", 3: "3", length:5}));
The question arised, why Array.prototype.slice.call does not work. Basically because a length property is missing.
Only properties, which can be used as indices are used.
var o1 = {1: "1", 2: "2", 3: "3"},
o2 = {1: "1", 2: "2", 3: "3", length: 5},
o3 = {1: "1", 2: "2", 3: "3", abc: 42, length: 5},
o4 = {0: "0", 1: "1", 2: "2", 3: "3"};
o4.length=Object.keys(o4).length;
console.log(Array.prototype.slice.call(o1));
console.log(Array.prototype.slice.call(o2));
console.log(Array.prototype.slice.call(o3));
console.log(Array.prototype.slice.call(o4));
Note: Dynamic length of properties-in-object could be assigned using Object.keys(OBJECT). The cause of getting undefined in console is missing property at index 0

var list = [];
for (item in obj) {
list.push(obj[item]);
}
//use list.push(parseInt(obj[item])) for number array
You can also do the following if you want it straight
Object.values(obj);

multidimensional arrays javascript

I have a multidimensional object in JavaScript with the following structure:
arg: Array[2]
2.0: "can_be_whatever"
3.1: Array[6]
1.0: Array[1]
1.0: Object
1. conc: false
2. followers: Array[1]
3. altVec: Array[0]
4. parents: Array[0]
5. regMsgs: Array[0]
6. shared: Array[0]
7. sharedWith: Array[0]
8. consistsof: Array[3]
1. 0: Array[1]
1. 0: "a"
2. length: 1
3. __proto__: Array[0]
2. 1: Array[1]
1. 0: "a"
2. length: 1
3. __proto__: Array[0]
3. 2: Array[1]
1. 0: "a"
2. length: 1
3. __proto__: Array[0]
4. length: 3
5. __proto__: Array[0]
9. unregMsgs: Array[0]
10. part: 0
11. __proto__: Object
I am quite new in JavaScript and i need to fetch the values "a" from the nested arrays. Can somebody propose something?

Frankly, this structure doesn't make any sense to me. I tried to "convert" it into a "real" JavaScript structure. I hope this gets close to what you meant:
var arg = [
"can_be_whatever",
[[{
conc: false,
followers: [null],
altVec: [],
parents: [],
regMsgs: [],
shared: [],
sharedWith: [],
consistsof: [["a"], ["a"], ["a"]],
unregMsgs: []
}], null, null, null, null, null]
];
You can then select the "a" values like so:
var consistsof = arg[1][0][0].consistsof;
for (var i = 0; i < consistsof.length; ++i) {
console.log(consistsof[i][0]);
}
In JavaScript you can select values from an array using [index] (just like in any other programming language) and properties from an object using .property (like in Java).