Dart Futures

What are Dart Futures?

Dart Futures represent a potential value or error that will be available at some time in the future. They are a core part of Dart's asynchronous programming model and are used to handle operations that take an unknown amount of time to complete, like fetching data from the internet or reading a file.

Creating a Future

You can create a Future in Dart using the Future class. A simple way to create a Future is by using the Future.delayed constructor, which completes with a value after a specified duration. Here's an example:

Handling Future Completion with then

Once a Future completes, you can execute some code using the then method. The then method allows you to define a callback that will be triggered with the Future's result.

Error Handling with catchError

Errors in Futures can be handled using the catchError method. This method allows you to define a callback that will be executed if the Future completes with an error.

Chaining Futures

Futures can be chained together to perform a series of asynchronous operations sequentially. This is done by returning a new Future from within a then callback.

Conclusion

Dart Futures provide a powerful mechanism for handling asynchronous operations. By using then and catchError, you can manage the flow of async tasks efficiently, ensuring your Dart applications remain responsive. Understanding Futures is crucial before moving on to more advanced concepts like async and await, which will be covered in the next post.