What does promise do?

The function of promise is to handle asynchronous operations. It provides a way to organize and manage the results of asynchronous operations and allows operations to be performed at a certain point in time, which allows developers to write asynchronous code more clearly and have better control over its execution flow. Promise also provides an error handling mechanism that can capture and handle errors when an asynchronous operation occurs. If the Promise is rejected (that is, the asynchronous operation fails), then an error handling function can be added to the Promise chain to handle this error, which makes the code more robust and reliable.

Operating system for this tutorial: Windows 10 system, Dell G3 computer.

In the program, the main function of Promise is to handle asynchronous operations. It provides a way to organize and manage the results of asynchronous operations and allows operations to be performed at a certain point in time, which allows developers to write asynchronous code more clearly and have better control over its execution flow.

Promise provides a mechanism to queue asynchronous operations, which means that multiple asynchronous operations can be executed in the expected order. When the asynchronous operation is completed, the Promise will return a result value, which can be used for further processing or other operations.

In addition, Promise also provides an error handling mechanism that can capture and handle errors when an asynchronous operation occurs. If the Promise is rejected (that is, the asynchronous operation fails), then an error handling function can be added to the Promise chain to handle this error, which makes the code more robust and reliable.

In short, Promise is very important in front-end development. It provides an effective way to handle asynchronous operations, making the code clearer, easier to understand and maintain.

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