useCustom Hooks

The term "useCustom" is often used as a placeholder or convention to represent a custom hook that you create yourself.

Custom hooks are a way to reuse logic or stateful behavior across multiple components in a React application. By convention, custom hooks start with the word "use" to indicate that they follow the rules of hooks and can be used within other functional components.

When you create a custom hook, you can define any functionality or state management logic you need. Custom hooks can encapsulate complex behavior, abstract away repetitive tasks, or manage shared state.

Here's an example of how you can create a custom hook:

In this example, the useCustomHook custom hook is created using the useState and useEffect hooks provided by React. It manages a value state and defines increment and decrement functions to update the value. The useEffect hook is used to log a message whenever the value changes.

To use the custom hook in a component, you can invoke it like any other hook:

In this example, the useCustomHook is used within the MyComponent component to manage the value state and provide the increment and decrement functions.

By creating and using custom hooks, you can encapsulate reusable logic and state management patterns, making your code more modular and easier to maintain.

It's important to note that the name "useCustom" is just a convention, and you can name your custom hooks based on their specific functionality or purpose.

Now that we have covered all the important hooks, it is time to move on to the next best thing. And that is APIs.

In the next two sections, we will learn about the two important APIs in React.


React custom hooks are used when you want to reuse stateful logic across multiple components in a React application. Custom hooks can encapsulate complex logic and provide a clean and reusable way to manage state, side effects, or any other functionality.

Here are a few scenarios where you might use custom hooks:

  1. Reusing logic
    If you find yourself repeating the same logic in multiple components, you can extract that logic into a custom hook and reuse it wherever needed.
  2. Abstracting complex functionality
    Custom hooks can simplify complex functionality, making it easier to understand and maintain in your components.
  3. Sharing non-UI state
    Custom hooks can be used to share non-UI state, such as API calls, authentication, or local storage, across different components.
  4. Testing
    Custom hooks make it easier to test individual pieces of logic independently, as they can be tested in isolation.

Overall, custom hooks are a powerful tool for code reuse and abstraction in React applications. They promote clean and modular code, making your components more maintainable and easier to understand.

Custom hooks in React are a powerful tool for code reuse and abstraction. However, there are a few scenarios where using custom hooks may not be appropriate:

  1. When the logic is specific to a single component
    If the logic is tightly coupled to a single component and is unlikely to be reused elsewhere, it might be better to keep the logic within the component itself.
  2. When the logic depends on component state or props
    Custom hooks are meant to be independent of component-specific state and props. If the logic relies heavily on component-specific data, it might be more suitable to keep it within the component.
  3. When the logic is complex and not easily understandable
    If the logic is convoluted and hard to understand, it might be better to keep it within the component so that it can be easily comprehended and maintained by other developers.

Remember, the aim of custom hooks is to promote reusability and abstraction. If these goals are not met, it might be better to consider alternative approaches.

No, custom hooks don't share state by default. Each instance of a custom hook creates its own independent state. This means that if you use the same custom hook in multiple components, each component will have its own separate state. Custom hooks are designed to encapsulate reusable logic, not to share state between components. If you need to share state between components, you can use other techniques such as lifting state up, context, or a state management library like Redux.