Typescript - How to extract the objects inside an array of objects?

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6 Answers

typescriptinsideextractobjectsarray
90%

Destructuring is a useful feature of ES6, with it we can extract values from objects and arrays with ease,,Function Parameter Destructuring,Destructuring is a way of extracting values into variables from data stored in objects and arrays

Example_snippet/controller/utility/_typescript.js/ const obj = {first: 'Asim', la. . .
const obj = {
   first: 'Asim',
   last: 'Hussain',
   age: 39
};
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88%

Before we begin, let's take some time to understand what the arguments objects is,,MDN: arguments is an Array-like object accessible inside functions that contains the values of the arguments passed to that function

Example_snippet/controller/utility/_typescript.js/ // Merge Array [...array1, .... . .
// Merge Array
[...array1, ...array2]

// Clone Array
[...array]

// String → Array
[...'string']

// Set  → Array
[...new Set([1, 2, 3])]

// Node List → Array
[...nodeList]

// Arguments → Array
[...arguments]
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72%

The Array object has the following methods:,In ES2015, you can use the Array,of static method to create arrays with single element

Example_snippet/controller/utility/_typescript.js/ let arr = new Array(element0, . . .
let arr = new Array(element0, element1, ..., elementN)
let arr = Array(element0, element1, ..., elementN)
let arr = [element0, element1, ..., elementN]
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65%

Example_snippet/controller/utility/_typescript.js/ let arr = [ { name:"string. . .
let arr = [{
      name: "string 1",
      value: "this",
      other: "that"
   },
   {
      name: "string 2",
      value: "this",
      other: "that"
   }
];

let obj = arr.find(o => o.name === 'string 1');

console.log(obj);
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75%

Both string and array values contain, in addition to the length property, a number of properties that hold function values,,Reading a property that doesn’t exist will give you the value undefined

Example_snippet/controller/utility/_inside.js/ for (let node = list; node; no. . .
for (let node = list; node; node = node.rest) {}
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every array needs to be positioned in the right object (same order of option) – James Nov 13 '18 at 13:52 ,Firstly, I need to get an array of type like this types = ['color', 'size'], Then, I'll use this array inside a mat-select:,Secondly, I need to populate a array of options by filtering the variants array to find the correct type:,Thanks for contributing an answer to Stack Overflow!

Example_snippet/controller/utility/_inside.js/ variants = [ { type: 'c. . .
 variants = [{
       type: 'color',
       options: ['red', 'green', 'blue']
    },
    {
       type: 'size',
       options: ['M', 'G', 'GG']
    }
 ]
 types = [];
 options = [];
 ngOnInit() {
    this.variants.forEach(t => this.types.push(t.type));
 }
 typeChange(type: string) {
    const variant = this.variants.find(v => v.type === type);
    this.options = variant.options;
 }