6 Advanced React Techniques to Boost Your TypeScript Skills
Are you ready to take your React and TypeScript skills to the next level? Look no further! In this article, we’ll explore some advanced techniques that will help you build more powerful and scalable apps with these powerful technologies.
1. Strongly-typed redux with TypeScript
One of the key benefits of using TypeScript with React is the ability to define strong types for your redux store and actions. This can help catch bugs and make your code more maintainable in the long run.
Here’s an example of how you can define a strongly-typed reducer and action creators in TypeScript:
import { Action, ActionCreator, Reducer } from "redux"
// Define the action types as constants
export const INCREMENT = "INCREMENT"
export const DECREMENT = "DECREMENT"
// Define the action interfaces
interface IncrementAction extends Action {
type: typeof INCREMENT
}
interface DecrementAction extends Action {
type: typeof DECREMENT
}
// Define the combined action type
type CounterAction = IncrementAction | DecrementAction
// Define the action creators
export const increment: ActionCreator<IncrementAction> = () => ({
type: INCREMENT
})
export const decrement: ActionCreator<DecrementAction> = () => ({
type: DECREMENT
})
// Define the initial state
export interface CounterState {
count: number
}
const initialState: CounterState = {
count: 0
}
// Define the reducer
export const counterReducer: Reducer<CounterState, CounterAction> = (
state = initialState,
action
) => {
switch (action.type) {
case INCREMENT:
return { ...state, count: state.count + 1 }
case DECREMENT:
return { ...state, count: state.count - 1 }
default:
return state
}
}2. Async actions with redux-thunk and TypeScript
Sometimes you need to perform async operations in your redux actions, like fetching data from an API. That’s where redux-thunk comes in handy. It allows you to write action creators that return functions instead of plain objects, which can dispatch multiple actions and perform async logic.
Here’s an example of how you can use redux-thunk with TypeScript to fetch data from an API and update the store:
import { ActionCreator, Dispatch } from "redux"
import { ThunkAction } from "redux-thunk"
import { getData } from "./api"
// Define the action types as constants
export const REQUEST_DATA = "REQUEST_DATA"
export const RECEIVE_DATA = "RECEIVE_DATA"
export const RECEIVE_ERROR = "RECEIVE_ERROR"
// Define the action interfaces
interface RequestDataAction extends Action {
type: typeof REQUEST_DATA
}
interface ReceiveDataAction extends Action {
type: typeof RECEIVE_DATA
data: any
}
interface ReceiveErrorAction extends Action {
type: typeof RECEIVE_ERROR
error3. Render props with TypeScript
Render props is a technique in React where a component renders a prop that is a function. This can be useful for sharing logic between components without having to use higher-order components (HOCs) or props drilling.
Here’s an example of how you can use render props with TypeScript:
import React from "react"
interface MouseProps {
render: (state: { x: number, y: number }) => React.ReactNode
}
class Mouse extends React.Component<MouseProps> {
state = { x: 0, y: 0 }
handleMouseMove = (event: React.MouseEvent<HTMLDivElement>) => {
this.setState({
x: event.clientX,
y: event.clientY
})
}
render() {
return (
<div style={{ height: "100vh" }} onMouseMove={this.handleMouseMove}>
{this.props.render(this.state)}
</div>
)
}
}
const App = () => (
<Mouse
render={({ x, y }) => (
<h1>The mouse position is ({x}, {y})</h1>
)}
/>
)4. Higher-order components (HOCs) with TypeScript
Higher-order components (HOCs) are functions that take a component and return a new component with additional functionality. They can be useful for abstracting common logic or injecting props into a component.
Here’s an example of how you can use HOCs with TypeScript to add a simple loading indicator to a component:
import React from "react"
interface InjectedProps {
isLoading: boolean
}
const withLoadingIndicator = <P extends object>(
WrappedComponent: React.ComponentType<P>
) => {
type Props = P & InjectedProps
class WithLoadingIndicator extends React.Component<Props> {
render() {
const { isLoading, ...rest } = this.props as InjectedProps
if (isLoading) {
return <h1>Loading...</h1>
}
return <WrappedComponent {...rest as P} />
}
}
return WithLoadingIndicator
}
interface DataProps {
data: any
}
const DataComponent = (props: DataProps) => <h1>{props.data}</h1>
const EnhancedDataComponent = withLoadingIndicator(DataComponent)
const App = () => (
<EnhancedDataComponent data={"Hello World"} isLoading={false} />
)5. TypeScript decorators
Decorators is a feature in TypeScript that allows you to annotate and modify classes and their members. They can be useful for adding additional functionality or metadata to your code.
6. TypeScript and React Hooks
React Hooks is a feature in React that allows you to use state and other React features without writing a class component. They can be used with TypeScript by annotating the types of the hook variables.
Here’s an example of how you can use the useState hook with TypeScript:
import React, { useState } from "react"
interface FormState {
name: string
email: string
}
const Form = () => {
const [formState, setFormState] = useState<FormState>({
name: "",
email: ""
})
const handleChange = (event: React.ChangeEvent<HTMLInputElement>) => {
const { name, value } = event.target
setFormState({ ...formState, [name]: value })
}
return (
<form>
<label htmlFor="name">Name:</label>
<input
type="text"
id="name"
name="name"
value={formState.name}
onChange={handleChange}
/>
<br />
<label htmlFor="email">Email:</label>
<input
type="email"
id="email"
name="email"
value={formState.email}
onChange={handleChange}
/>
</form>
)
}There you have it, 6 advanced techniques for using React and TypeScript together to build powerful and scalable applications. Whether you’re a seasoned pro or a newcomer to these technologies, we hope you learned something new and can put these techniques to good use in your own projects. Happy coding!
