Upon upgrading from Angular 7 to Angular 10 and implementing TypeScript 4 or higher, I began receiving deprecation warnings for the functions isObject() and isNullOrUndefined() when running ng lint
The function isNullOrUndefined has been deprecated since version 4.0.0 - please use `value === null || value === undefined` instead.
The function isObject has been deprecated since version 4.0.0 - please use `value !== null && typeof value === 'object'` instead.
Why stick with the isNullOrUndefined() function when you can switch things up by using a type predicate:
function isDefined<T>(value: T | undefined | null): value is T {
return value !== undefined && value !== null;
}
function bar(foo: string | undefined | null) {
if (!isDefined(foo)) {
return undefined;
}
// With this type predicate, TypeScript recognizes that foo must be a string
return foo.split('.');
}
Check out this Typescript Playground Example
To solve the issue at hand, I took the initiative to create my own file called utilities.ts within the project structure under utils/utilities.ts. In this file, I defined and exported two essential methods.
/**
* Function created to replace deprecated isNullOrUndefined function
* @param value any
* @returns boolean
*/
export function checkIfNull(value: any) {
return value === null || value === undefined;
}
/**
* New function introduced as a replacement for deprecated isObject function
* @param value any
* @returns boolean
*/
export function verifyObject(value: any) {
return value !== null && typeof value === 'object';
}
I proceeded by making necessary changes to all import statements involving checkIfNull and verifyObject
import { checkIfNull, verifyObject } from 'util';
import { checkIfNull, verifyObject } from '@common/lib/utils/utilities';
I have encountered an issue with my code: browser.wait(ExpectedConditions.presenceOf(elementName)); Unfortunately, this often fails and only provides the vague message "expected true to be false", which is quite frustrating. When it fails, I need a more ...
Currently, I am in the process of configuring protobuf to work with typescript. According to the official Google Documentation, all that is needed is to execute npm install google-protobuf and then to include require('google-protobuf'). Unfortu ...
Is it necessary to bootstrap each component individually in this code snippet? import { bootstrap } from '@angular/platform-browser-dynamic'; import { AppComponent1 } from './app.component1'; import { AppComponent2 } from './app ...
Currently, I am delving into the documentation for an angular 4 project called "Tour of Heroes" which can be found at https://angular.io/docs/ts/latest/tutorial/toh-pt2.html. <li *ngFor="let hero of heroes" (click)="onSelect(hero)">{{hero.name}}< ...
I have a TypeScript file containing user data: File path: quickstart-muster/app/mock/user.mock.ts import {User} from "../user"; export const USERS:User[]=[ new User(....); ]; I have a service set up at: quickstart-muster/app/services/user.service.ts ...
In my ASP.Net Core 1.1 backend, CORS has been enabled as shown below: public void ConfigureServices(IServiceCollection services) { // Add framework services. services.AddDbContext<WebAPIDataContext>(options => { options.UseMyS ...
I am trying to extract the `s_id` field from this JSON data: { "StatusCode": 0, "StatusMessage": "OK", "StatusDescription": [ { "s_id": "11E8C70C8A5D78888E6EFA163EBBBC1D", "s_serial": " ...
Using Angular 6, I have implemented an API call in a service and subscribed to it in my controller. The data is successfully received, but I want to restructure it in the controller so that I can later pass it into a Chart JS chart. Here is the code snipp ...
Here is the given code snippet: import * as fs from 'fs'; import {promises as fsPromises} from 'fs'; // ... // Reading the file without encoding to access raw buffer. const { bytesRead, buffer as fileBuffer } = await fsPromises.read( ...
After extensive research, I discovered an intriguing performance enhancement technique in Angular: setting ChangeDetectionStrategy to OnPush. This method can effectively reduce the number of modifications within an Angular App. However, are there specific ...
Currently in the process of developing a chrome extension but encountering an issue with loading the json web token node module in my Node.js setup. background-script.ts import jwt from 'jsonwebtoken'; // import * as jwt from '../node_mod ...
Even after following the most recommended solutions online, I am still facing an issue that says Error: inject() must be called from an injection context. In addition to this error, I am also receiving multiple warnings such as: Warning: ###/src/ap ...
During the execution of my javascript async function, I encountered a situation where my printing code was running before the div creation. I needed to ensure that my print code would run only after the completion of the for loop, but I struggled to find a ...
When navigating to a page in my router, I make a REST API request to retrieve data from the server in the beforeEnter clause as shown below: beforeEnter: (to, form, next) => { getData().then( (response) => { ...
Description : I have implemented a dropdown list using element that contains a list of items along with a search field. This allows users to easily search for specific items in the list instead of manually scrolling through a long dropdown menu. They can ...
What causes the type of y to change to string only after the destruction of the object? const obj: { x: string; y: string | null } = {} as any const { x, y } = obj // y is string now ...
When developing a web app's back-end with TypeScript, I've found intersection types to be incredibly beneficial for optimizing SQL queries. Imagine having the following tables: User userId: number userEmail: string Post postId: number userId: ...
Hello, I'm currently working on a React component and facing an interesting challenge. Let's say I have an array structured like this: let data: {title: ReactNode}[] = [ {title: "test1"}, {title: <Component1 title="test2& ...
I am working on a form array that generates form controls for each row along with a button. The challenge I'm facing is to disable the button associated with a row if the form group related to that row in the form array is not valid. Here is the but ...
Currently working on an Angular 8 application that utilizes the prime ng editor. I am looking to set limits for image size and dimensions before uploading via the upload image button, but encountering difficulties in implementing this feature. https://i.s ...