React useContext() Hook Quiz
What is the purpose of the useContext hook in React.js?
The useContext hook in React.js is used to consume a context value.
When using the useContext hook in React.js, what is the primary purpose of the context provider?
The context provider in React.js is primarily responsible for providing the context value to its descendants in the component tree, allowing them to consume the context using the useContext hook.
How do you create a context in React.js?
Context is created using the createContext function.
In a functional component, how do you consume a context using the useContext hook?
The correct syntax to consume context in a functional component is const context = useContext(ContextName);
How can you provide a default value to a context using the useContext hook in React.js?
To provide a default value to a context when using useContext, you can use the defaultValue prop in the Context.Provider component.
Can you use the useContext hook inside a class component?
The useContext hook is designed for functional components and cannot be used directly in class components.
What happens if the context provider is not present in the component tree when using useContext?
If the context provider is not present, the useContext hook returns undefined.
How do you provide a context value using the Context.Provider component?
The correct syntax to provide a context value is <Context.Provider value={contextValue}>...</Context.Provider>.
What is the purpose of the defaultValue parameter in the createContext function?
The defaultValue parameter is used to set a default value for the context when no provider is found in the component tree.
How can you access the context value outside of the render function in a functional component?
To access the context value outside of the render function, you can create a separate custom hook.
In the useContext hook, what should be passed as an argument to identify the context to be consumed?
The argument passed to useContext is the context itself, which is identified by its name.
What is the purpose of the displayName property when defining a context with createContext?
The displayName property provides a custom name for the context, mainly used for debugging purposes.
How can you update the context value dynamically using the useContext hook?
Context values can be updated dynamically using the setContext method.
When using multiple contexts in a component, how do you consume them using useContext?
To consume multiple contexts, you should call useContext for each context separately.
What is the purpose of the Provider component in the context API?
The Provider component is used to provide the context value to its descendants in the component tree.
How can you use the useContext hook in a class component?
The useContext hook is designed for functional components and cannot be used directly in class components.
What is the purpose of the useContext hook in the component lifecycle?
The useContext hook is not directly related to the component lifecycle; it is used to consume a context value.
How can you share state logic between components using useContext?
To share state logic between components, you can define a context that holds the shared state.
In a context provider, how can you provide multiple values to different parts of the component tree?
You can provide multiple values to different parts of the component tree using the value prop with an object containing those values.
What happens if you nest multiple context providers in the component tree?
When nesting context providers, the innermost provider overrides the values of the outer providers.