React TypeScript Cheat Sheet

React is a popular JavaScript library for building user interfaces, while TypeScript is a superset of JavaScript that adds static typing and other features to the language. Together, they form a powerful combination for building robust web applications.

TypeScript provides several benefits over plain JavaScript, including better code organization, improved code readability, and enhanced error checking. By adding static typing to JavaScript, TypeScript helps catch errors at compile time rather than runtime, which can save developers time and effort in debugging.

React, on the other hand, provides a declarative approach to building user interfaces, making it easier to manage complex UI components. With React, developers can create reusable UI components that can be easily composed to build complex applications.

When combined, React and TypeScript provide a powerful toolset for building scalable and maintainable web applications. TypeScript’s static typing helps catch errors early in the development process, while React’s declarative approach simplifies the creation of complex UI components.

This cheat sheet provides an extensive list of React TypeScript concepts and their descriptions.

Table of Contents

React Components

ConceptDescription
Function ComponentA component that is defined as a function. It takes in props as an argument and returns JSX.
Class ComponentA component that is defined as a class. It has a render method that returns JSX.
Pure ComponentA component that only re-renders when its props or state change.
Higher-Order ComponentA function that takes in a component and returns a new component with additional functionality.
Render PropA technique for sharing code between components using a prop whose value is a function.

Props and State

ConceptDescription
PropsShort for “”properties””, props are read-only data that are passed down from a parent component to a child component.
StateData that is managed within a component and can be changed over time.
setStateA method used to update the state of a component. It takes in an object that represents the new state.
defaultPropsA property that can be set on a component to provide default values for its props.
propTypesA property that can be set on a component to define the types of its props.

Hooks

ConceptDescription
useStateA hook that allows a functional component to use state. It returns an array with the current state value and a function to update it.
useEffectA hook that allows a functional component to perform side effects. It takes in a function that will be executed after every render.
useContextA hook that allows a functional component to access a context object.
useRefA hook that returns a mutable ref object that can be used to store a value across renders.
useReducerA hook that allows a functional component to use a reducer function to manage state.
useCallbackA hook that returns a memoized callback function.
useMemoA hook that returns a memoized value.

Event Handling

ConceptDescription
onClickAn event that is triggered when an element is clicked.
onChangeAn event that is triggered when the value of an input element changes.
onSubmitAn event that is triggered when a form is submitted.
onKeyPressAn event that is triggered when a key is pressed down.
onKeyUpAn event that is triggered when a key is released.

Conditional Rendering

ConceptDescription
if statementA JavaScript statement that allows for conditional rendering.
ternary operatorA shorthand way of writing an if statement.
&& operatorA shorthand way of writing an if statement that only renders if a condition is true.
switch statementA JavaScript statement that allows for multiple conditional renderings.

Lists and Keys

ConceptDescription
map methodA JavaScript method that allows for rendering a list of items.
key propA prop that is used to give each item in a list a unique identifier.
indexA value that is automatically assigned to each item in a list.

Forms

ConceptDescription
Controlled ComponentA form element that is controlled by React state.
Uncontrolled ComponentA form element that is not controlled by React state.
onSubmitAn event that is triggered when a form is submitted.
onChangeAn event that is triggered when the value of an input element changes.

Lifecycle Methods

ConceptDescription
componentDidMountA method that is called after a component is mounted.
componentDidUpdateA method that is called after a component is updated.
componentWillUnmountA method that is called before a component is unmounted.

TypeScript Interfaces

ConceptDescription
InterfaceA TypeScript construct that defines the shape of an object.
Props InterfaceAn interface that defines the props of a component.
State InterfaceAn interface that defines the state of a component.

TypeScript Generics

ConceptDescription
GenericA TypeScript construct that allows for the creation of reusable code.
React.FCA generic type that defines a function component.
React.ComponentA generic type that defines a class component.

References