Javascript Promis

JavaScript promises are one of the convenient ways to manage asynchronous operations. promises represent values that may be fulfilled or fail in the future. They are used to manage the results of asynchronous operations and reduce problems with callback functions.

promis table

promises

Promise constructor is used to create a promise in JavaScript.

• resolve
• reaject

resolve and reject functions are used to control the result of JavaScript promises asynchronous operations.

resolve

resolve function is called when a promise is successfully executed. This function takes a value as an argument, and this value is then passed to the .then() method.

In the above example, if the success variable is true, the resolve function is called and "This operation completed successfully!" transmits the value.

then method:

reject

reject function is called when a promise fails. This function takes as an argument the information about an error or failure, and this value is then passed to the .catch() method.

In the above example, if the success variable is false, the reject function is called and "This operation failed." transmits the value.

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