We will explain how to add and subtract dates and times using JavaScript .
How can I execute multiple processes in sequence when doing asynchronous processing?
The then method allows you to perform multiple asynchronous operations in sequence.
How to execute multiple asynchronous processes in sequence using the then method
When performing asynchronous processing, use the then method to execute multiple processes in sequence.
Since the then method returns a Promise object, you can perform the following asynchronous process by calling the then method of that Promise object.
// Asynchronous processing 1
let promise1 = new Promise((resolve) => {
setTimeout(() => {
console.log("Asynchronous processing 1 completed");
resolve();
}, 1000);
});
// Asynchronous processing 2
let promise2 = new Promise((resolve) => {
setTimeout(() => {
console.log("Asynchronous processing 2 completed");
resolve();
}, 2000);
});
// Execute asynchronous processing 1, and after completion, execute asynchronous processing 2
promise1.then(() => {
return promise2;
}).then(() => {
console.log("All asynchronous processing completed");
});
It is written to execute asynchronous process 1 and execute asynchronous process 2 after completion. Call the then method on promise1 and return promise2 within it. After that, the then method is called and the string “All asynchronous processing is completed” is output.
In this way, by using the then method, you can perform asynchronous processing in sequence.
summary
“How to execute multiple asynchronous processes in sequence” is summarized below.
- Use the then method to execute multiple processes in sequence when performing asynchronous processing in JavaScript.
- The then method returns a Promise object.
- The next asynchronous process can be executed by calling the then method.
We were able to execute asynchronous processing sequentially using the then method!
When performing asynchronous processing using the then method, be sure to write only the necessary processing using the then method.
This makes the process easier to understand and easier to maintain.
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