What are the forms of promise?
Promise forms are: 1. Promise.resolve(value): Returns a Promise object that is resolved with a given value; 2. Promise.reject(value): Returns a Promise that is rejected with a given value. Object; 3. new Promise(executor): Create a new Promise object and accept an executor function as a parameter.
Operating system for this tutorial: Windows 10 system, Dell G3 computer.
Promise has three main forms in JavaScript:
Promise.resolve(value): Returns a Promise object that is resolved with a given value.
Promise.reject(value): Returns a Promise object that is rejected with the given value.
new Promise(executor): Create a new Promise object and accept an executor function as a parameter. The executor function accepts two parameters: resolve and reject, which are used to define the state of the Promise object.
In addition, there are three states of Promise objects:
pending (in progress): initial state, neither success nor failure state.
fulfilled (successful): Indicates that the operation was successfully completed.
rejected (failed): Indicates that the operation failed.
The above information is for reference only. If you still have questions, it is recommended to consult professional JavaScript books or consult professional front-end developers.
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