Creating an array in TypeScript and determining its type as an object

Currently, I am in the process of creating an app with Ionic, utilizing TypeScript as the primary language.

When declaring an array in my code:

products = new Array();

I expect it to be recognized as an array. However, when I check the type using console.log(typeof this.products), it returns "object".

Is there any way I can ensure that it is recognized as an array instead? Any suggestions or solutions?

Answer №1

typeof [] returns object because an array is not a defined data type in JavaScript.

To determine if your variable is an array, you can use .isArray()

var arr1 = Array.isArray([1, 2, 3]);  
var arr2 = Array.isArray({foo: 123}); 

console.log(arr1);
console.log(arr2);

Alternatively, you can also utilize instanceof

var arr1 = [1,2,3];
if(typeof arr1 === "object" && arr1 instanceof Array){
  console.log("It is an array");
}

Similar questions

If you have not found the answer to your question or you are interested in this topic, then look at other similar questions below or use the search

Do the "Save to Drive" buttons require manual cleaning?

Utilizing the Google Drive API for JavaScript within a VueJS application can be done as follows: In your index.html <script type="text/javascript"> window.___gcfg = { parsetags: 'explicit', lang: 'en-US' }; </scri ...

The 'Icon' JSX component does not contain any construction or call signatures

I am currently learning typescript and facing an issue while working on a sidebar navigation feature. I have an array containing menu items with icons that I need to display. Here is the array: const menuItems = [ { id: 1, label: "Dashboard", icon: <Co ...

Is there a way to incorporate innerhtml (or innertext) with the h() function for adding content?

Due to certain requirements, I need to utilize virtual DOM. Below is the code snippet that I am working with: // test.js import { h, ref } from 'vue' const ButtonCounter = { name: 'button-counter', props: { tag: { type: S ...

AngularJS service for exchanging information among controllers

I am working on an AngularJS application (1.4.10) where I need to share data between two controllers. To achieve this, I created a factory: .factory('CardsForService', function($http, URL){ var service = { "block_id": '', ...

Inquiring about JavaScript's substring method in String.prototype

let vowels = "AEIOU"; let result = vowels.substring(0, 3); document.write(result); I'm puzzled as to why the output is AEI instead of AEIO. Is this due to the indexing starting from zero in programming languages? ...

What is the best way to integrate ag-grid with Observable in Angular 2?

After conducting extensive research on the Internet, I am still struggling to connect the pieces. My angular2 application utilizes an Observable data source from HTTP and I am attempting to integrate ag-grid. However, all I see is a loading screen instead ...

Guide on determining if the value in a JSON object is a string or an array in Node.js

Running a Node.js application, I encountered the following JSON array structure. First JSON object: var json1= { bookmarkname: 'My Health Circles', bookmarkurl: 'http://localhost:3000/', bookmark_system_category: [ '22&apos ...

Physically moving the window to a specified location using window.scrollTo()

Whenever I use the window.scrollTo(); method upon clicking a button, it simply jumps to the destination without displaying the scrolling motion. How can I ensure that the window physically scrolls to the designated position instead of instantly appearing ...

Utilizing Multiple Canvases Simultaneously

I'm facing an issue where I need to crop multiple images on a single page using the canvas tag in HTML5 along with JavaScript. However, only one image is displaying on the page. How can I resolve this? The code snippet that I have attempted is provid ...

Employing Modernizer.js to automatically redirect users to a compatible page if drag and drop functionality is not supported

I recently set up modernizer.js to check if a page supports drag and drop functionality. Initially, I had it set up so that one div would display if drag and drop was supported, and another div would show if it wasn't. However, I ran into issues with ...

Update the default window location when the Browse button is clicked

When a user clicks on the browse button on our webpage to upload a file, I want to change the window location. Currently, when the button is clicked, a window pops up defaulting to "My Documents". However, I would like to change this so that when the user ...

Can a JSON interface be integrated into a c# application?

I have successfully created a basic C# application (.Net 4.0 + WPF) that is capable of sending and receiving JSON messages through TCP sockets. Now, I am looking to enable JavaScript applications on websites and PHP scripts to communicate with my app by s ...

Issue: The module "Angular" cannot be found in the Swiper package, resulting in an "ionic2-calendar Error

I recently updated the package for my project Utilizing Ionic and Angular to create applications for iOS and Android Current versions: Ionic 7, Angular 16 Following a recommendation, I made the switch from 'ion-slides' to the Swiper.js library ...

tips for applying a where clause on a jsonb column in an included table with sequelize

I currently have 2 tables stored in a postgres database. Table_A -------- id BIGINT metadata JSONB Table_B -------- id BIGINT a_id BIGINT metadata JSONB Data Table_A id | metadata 1 | {'gender': 'Male', 'name': 'xyz&ap ...

Trouble in Jest: Async test error

I encountered a specific error message that reads: Cannot read property 'indexOf' of undefined at Function.isPendingSpecException After some investigation, I pinpointed the problem to this particular line of code: TokenRepositor ...

Transform the default WordPress gallery into a stunning slideshow with FlexSlider 2 integration

Greetings, I am searching for a solution to modify the default WordPress gallery in order to integrate the FlexSlider 2 plugin. I specifically want to incorporate this module or feature from this link, but I have been unable to figure it out myself. Your ...

System for Node.js execution replay logging

Running a straightforward script that performs various tasks can be tedious when trying to debug errors. The log messages scattered throughout the code clutter the file, requiring more and more console.log entries for detailed information. Instead of fill ...

receiving an error message due to attempting to access an

I'm facing an issue with replacing objects in an array using JavaScript. I tried to use indexOf and splice methods, but it's not working as expected. The value returned by indexOf is '-1', indicating that the object is not found in the ...

Bootstrap Datepicker allows you to set a maxdate of 2 days from the initial date selected

Imagine this scenario: when I choose a date for Check-In on May 10th, I want the Check-Out section to automatically show May 10th selected as well, with the following 2 days available and the rest disabled. If you're looking for documentation, you ca ...

Error when compiling TypeScript: The callback function provided in Array.map is not callable

This is a Node.js API that has been written in Typescript. app.post('/photos/upload', upload.array('photos', 12), async (req, res) => { var response = { } var list = [] try { const col = await loadCollection(COLLECTION_NAM ...