Prop drilling, also known as “prop-chain” or “prop-tunneling,” refers to the practice of passing props down through multiple levels of components in a React application in order to make those props available to a deeply nested component. This can become problematic as the depth of the component tree increases and the props need to be passed through multiple levels of components that do not actually use them.
One example of why prop drilling is bad is that it can lead to a lot of unnecessary props being passed around in your application, which can make your code harder to understand and reason about. When props are passed through multiple levels of components, it can become difficult to know exactly where a particular prop is being used, which can make it hard to track down bugs or make changes to your code.
Another example is the increase in complexity, when a component deep down in the component tree needs to use a prop that is not being passed to it directly, the component will have to pass the prop up through all of its parents until it reaches a component that does have access to the prop. This can make your component tree more complex and harder to understand.
In addition, if the prop is only used by a single child component, it is not appropriate to pass it down through all the parents just to get to it.
To mitigate prop drilling, React has features such as React Context API, React Hooks and HOC (Higher Order Component) that can help to minimize or avoid prop drilling.
For example, you can use React’s context API to create a “context” that can be accessed by any component in your application, regardless of its position in the component tree. This makes it easy to share data between components without having to pass it down through multiple levels of components.
Another way is to use hooks such as useContext,useReducer and useState to share state between components without drilling the props.
HOCs are also a way to share props between components without drilling the props, it is a higher-order component that provides a particular piece of state or behaviour to any other component that renders it. This allows you to share props without drilling them down through multiple levels of components.
In summary, prop drilling can make your code harder to understand and reason about, increase the complexity of your component tree, and make it difficult to manage state and props in a large application.
It is best to practice using the available React features to avoid or minimize prop drilling.