What are loadable components?
- A component that loads data asynchronously
- A component that loads other components asynchronously
- A component that loads itself asynchronously
- A component that loads CSS stylesheets asynchronously
Loadable components are a way to load other components asynchronously in React. Loadable components allow components to be split into smaller chunks and loaded on-demand, improving performance and reducing initial load times. Loadable components are typically used with dynamic imports to enable asynchronous loading of code.
What are React Mixins?
- Components that are composed of other components
- Methods for handling async operations in React
- Reusable code snippets that can be applied to multiple components
- Techniques for improving the performance of React applications
React Mixins are reusable code snippets that can be applied to multiple components in order to provide shared functionality. They are a way to encapsulate logic and behavior that can be used across multiple components, allowing for code reuse and reducing duplication. However, they are not recommended in modern versions of React and have been largely replaced by higher-order components and render props.
What is Formik?
- A React library for working with forms
- A testing library for React
- A utility library for working with arrays
- An animation library for React
Formik is a utility library for working with forms in React. It provides a simple and flexible way to handle form validation, input masking, and submission handling. Formik also integrates with other popular form libraries, such as Yup and React-Select.
What is a consumer?
- A component that provides a context value
- A component that consumes a context value
- A component that renders children conditionally
- A component that handles user events
In React context, a consumer is a component that consumes a context value. The consumer component allows child components to access the context value without the need to pass props explicitly. Consumers can be implemented using the useContext() hook or the Consumer component, which provides a render prop that can be used to consume the context value.
How do you conditionally render components?
- Use the "if" statement in JSX
- Use the "render" method in JSX
- Use the switch statement in JSX
- Use the ternary operator in JSX
To conditionally render components in React, you can use the ternary operator in JSX. This allows you to specify a condition, and render one component if the condition is true, and another component if the condition is false. You can also use other conditional statements, such as "if" statements or switch statements, outside of the JSX to determine which component to render.
What is the mental model of redux-saga?
- Asynchronous call stack
- Finite state machine
- Observer pattern
The mental model of redux-saga is that of a finite state machine. It allows you to define a sequence of steps for handling a specific side effect and provides a way to manage the state of that sequence. This makes it easier to reason about and test complex logic in your Redux application.
What is the proper way to access Redux store?
- Use the getState() method
- Use the connect() function
- Use the Provider component
- Use the useContext() hook
The proper way to access the Redux store is to use the connect() function provided by React Redux. This allows you to connect a component to the store and access its state and dispatch functions.
What is the purpose of the constants in Redux?
- To make the code easier to read and understand
- To prevent changes to the action types
- To enable minification and other performance optimizations
Constants in Redux are used to define action types, which are used to identify the type of action being dispatched to the Redux store. By using constants, you can prevent unintended changes to the action types and make it easier to understand the purpose of each action.
What is a switching component?
- A component that animates between different states
- A component that changes its state based on user input
- A component that provides an interface for switching between different pages
- A component that switches between multiple child components
A switching component in React is a component that renders one of several child components based on some condition or state. This is commonly used to switch between different views or user interface elements in response to user input or other events.
How Redux Form initialValues get updated from state?
- initialValues are automatically synced with the Redux store
- You need to manually update initialValues in the form component
- initialValues are passed in as a prop to the form component
The initialValues prop in Redux Form is used to set the initial values for the form fields. You can pass in an object of initial values as the initialValues prop, which will be used to populate the form fields when the form is first rendered. The initialValues can be sourced from the Redux store, and can be updated by dispatching an action that updates the relevant values in the store. The form component will automatically update when the initialValues prop changes.
How to conditionally apply class attributes?
- Using the "class" attribute and a ternary operator
- Using the "class" attribute and an if statement
- Using the "className" attribute and a ternary operator
- Using the "className" attribute and an if statement
In React, you can conditionally apply class attributes by using the "className" attribute and a ternary operator. This allows you to add or remove classes based on some condition, such as the state of the component. The "className" attribute is used instead of the "class" attribute in React, because "class" is a reserved keyword in JavaScript.
What is the purpose of forward ref in HOCs?
- To forward props to child components
- To forward the ref to child components
- To wrap child components with additional functionality
- To wrap child components with a higher-order component
Forwarding refs in Higher-Order Components (HOCs) is a technique for passing a ref from a parent component to its child components. This allows the child components to access the DOM node or React element that the ref is attached to. To forward a ref in an HOC, the HOC component should use the forwardRef() method to create a new component that can receive a ref. The new component can then be used to wrap the child components and pass the ref through to the child components.