Resolving the Expected 0 arguments, but got 1 Error in Redux with TypeScript

Learn how to fix the Redux error: `Expected 0 arguments, but got 1` in your React application using TypeScript. Understand the correct use of hooks and dispatching actions.
---

Visit these links for original content and any more details, such as alternate solutions, latest updates/developments on topic, comments, revision history etc. For example, the original title of the Question was: Expected 0 arguments, but got 1 in redux with typescript

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
Resolving the Expected 0 arguments, but got 1 Error in Redux with TypeScript

When working with Redux and TypeScript in a React application, you might come across errors related to using async thunks and dispatch functions. One such error is: "Expected 0 arguments, but got 1". This issue typically arises when you are not correctly utilizing the dispatch hook provided by Redux in your components. In this guide, we’ll delve into what this error means and how to resolve it effectively.

Understanding the Problem

You are trying to fetch an item using an async thunk function but encounter the error when dispatching the action with an argument. Here’s a snippet of the code that causes this issue:

[[See Video to Reveal this Text or Code Snippet]]

In your React component, you have implemented the handleFetch function to fetch the item based on the id from an event:

[[See Video to Reveal this Text or Code Snippet]]

This results in the error because the useAppDispatch hook is being invoked with an argument, which it is not designed to accept.

What Causes This Error?

Misuse of the useAppDispatch Hook: Hooks in React must be invoked within the body of a functional component. They cannot be called conditionally or nested inside another function.

Passing Arguments Improperly: The useAppDispatch hook itself does not take any arguments, but you are trying to pass the action as an argument, leading to the error.

Correcting the Usage of Redux Dispatch

To solve this problem, you'll need to properly utilize the useAppDispatch hook in your component. Here's how to do it, step-by-step:

Step 1: Call useAppDispatch Directly in your Component

[[See Video to Reveal this Text or Code Snippet]]

This line should be placed directly in the body of your component, outside of any functions.

Step 2: Modify the handleFetch Function

Update your handleFetch function to use the dispatch returned by the hook to call fetchItem:

[[See Video to Reveal this Text or Code Snippet]]

Updated Component Example

Here’s how your component might look after these corrections are made:

[[See Video to Reveal this Text or Code Snippet]]

Conclusion

By making these adjustments, you can avoid the Expected 0 arguments, but got 1 error in your Redux application using TypeScript. It’s crucial to understand the rules of hooks in React and how to properly handle dispatching actions in Redux. By organizing your code this way, you can streamline your async calls and keep your codebase clean and functional.

If you have any questions or further issues, feel free to reach out or leave a comment below!