Introducing a new element in TypeScript using a separate method with parameters

Question

Introducing a new element in TypeScript using a separate method with parameters

Currently, I am attempting to create a method that will allow me to add an element to my array. Despite being new to typescript, I have been struggling to determine what needs to go into the addNewProduct function. While seeking help, I came across the push function, but when implemented, it gives an error message stating "not applicable on type {}".

class ProductsComponent {

 title = 'Products List';

 products: any[] = [
   {
     'name': 'a',
     'quantity': 20
   },
   {
     'name': 'b',
     'quantity': 200
   }
 ];

constructor(){
  // Printing the current Product Array
  this.addNewProduct('c', 50 );
  // Printing the new Array
}
 addNewProduct(name: string, quantity: number) {
   // Code for adding a new product
 }

}

typescript

Answer 1

Answer №1

Have you experimented with something along these lines:

class AppComponent {

 title = 'Products List';

 products = [
   {
     'name': 'a',
     'quantity': 20
   },
   {
     'name': 'b',
     'quantity': 200
   }
 ];

constructor(){
  // Display the current Product Array
  this.addNewProduct('c', 50 );
  // Display the new Array
}
 addNewProduct(name: string, quantity: number) {
   // code
     this.products.push({name: name,quantity : quantity}); //< -- ADD A NEW OBJECT WITH ARGUMENT PARAMETERS TO YOUR ARRAY PROP (products)
 }

}

BE CAREFUL .. If you encounter an error as described (

property 'push' does not exist on type {}

) ... it means you are attempting to use push method on an object ..

Therefore, double check your products array .. It may NOT be an array..

It might be like this instead:

products = { \\< -- make sure here if you have [ or {
   {
     'name': 'a',
     'quantity': 20
   },
   {
     'name': 'b',
     'quantity': 200
   }
 }; // < -- confirm again here if you have ] or }

I hope this assists you!!

Answer 2

Have you experimented with something along these lines:

class AppComponent {

 title = 'Products List';

 products = [
   {
     'name': 'a',
     'quantity': 20
   },
   {
     'name': 'b',
     'quantity': 200
   }
 ];

constructor(){
  // Display the current Product Array
  this.addNewProduct('c', 50 );
  // Display the new Array
}
 addNewProduct(name: string, quantity: number) {
   // code
     this.products.push({name: name,quantity : quantity}); //< -- ADD A NEW OBJECT WITH ARGUMENT PARAMETERS TO YOUR ARRAY PROP (products)
 }

}

BE CAREFUL .. If you encounter an error as described (

property 'push' does not exist on type {}

) ... it means you are attempting to use push method on an object ..

Therefore, double check your products array .. It may NOT be an array..

It might be like this instead:

products = { \\< -- make sure here if you have [ or {
   {
     'name': 'a',
     'quantity': 20
   },
   {
     'name': 'b',
     'quantity': 200
   }
 }; // < -- confirm again here if you have ] or }

I hope this assists you!!

Answer 3

Answer №2

Check out this Javascript example, perfectly compatible with Typescript as well. The code snippet showcases the Object Literal Property Value Shorthand, a handy way to quickly create an object and append it to an array.

This shorthand method involves skipping the value assignment when both the key and the value share the same name:

const greeting = 'hello';
const obj = { greeting: greeting };

is equivalent to:

const greeting = 'hello';
const obj = { greeting };

resulting in:

{ greeting: 'hello' }

Take a look at this push example below:

class ProductsComponent {
  constructor() {
    this.products = [{
      name: 'a',
      quantity: 20
    },
    {
      name: 'b',
      quantity: 200
    }];

    this.addNewProduct('c', 50 );
  }

  addNewProduct(name, quantity) {
    this.products.push({ name, quantity });
  }
}

const comp = new ProductsComponent();
console.log(comp.products);

Answer 4

Check out this Javascript example, perfectly compatible with Typescript as well. The code snippet showcases the Object Literal Property Value Shorthand, a handy way to quickly create an object and append it to an array.

This shorthand method involves skipping the value assignment when both the key and the value share the same name:

const greeting = 'hello';
const obj = { greeting: greeting };

is equivalent to:

const greeting = 'hello';
const obj = { greeting };

resulting in:

{ greeting: 'hello' }

Take a look at this push example below:

class ProductsComponent {
  constructor() {
    this.products = [{
      name: 'a',
      quantity: 20
    },
    {
      name: 'b',
      quantity: 200
    }];

    this.addNewProduct('c', 50 );
  }

  addNewProduct(name, quantity) {
    this.products.push({ name, quantity });
  }
}

const comp = new ProductsComponent();
console.log(comp.products);

Introducing a new element in TypeScript using a separate method with parameters

Answer №1

Answer №2

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