async/await ב-JavaScript

1async function myAsyncFunction() {
2    // Write asynchronous processing here
3    return 'Result';  // Return a Promise
4}

1async function greet() {
2    return 'Hello, World!';
3}
4
5greet().then((message) => {
6    console.log(message);  // Displays "Hello, World!"
7});

 1async function fetchData() {
 2    // Wait for the result of the Promise
 3    const data = await fetch('https://codesparklab.com/json/example.json');
 4    // Wait for the asynchronous operation to complete
 5    const jsonData = await data.json();
 6    // Retrieve and display the data
 7    console.log(jsonData);
 8}
 9
10fetchData();

 1async function fetchData() {
 2    try {
 3        // Invalid URL
 4        const data = await fetch('https://invalid.codesparklab.com/');
 5        const jsonData = await data.json();
 6        console.log(jsonData);
 7    } catch (error) {
 8        // Catch the error
 9        console.error('Failed to fetch data:', error);
10    }
11}
12
13fetchData();

 1// Code using Promise chains
 2function fetchDataPromise() {
 3    fetch('https://codesparklab.com/json/example.json')
 4        .then((response) => response.json())
 5        .then((data) => {
 6            console.log(data);
 7        })
 8    .catch((error) => {
 9        console.error('Failed to fetch data:', error);
10    });
11}
12
13// Code using async/await
14async function fetchDataAsync() {
15    try {
16        const response = await fetch('https://codesparklab.com/json/example.json');
17        const data = await response.json();
18        console.log(data);
19    } catch (error) {
20        console.error('Failed to fetch data:', error);
21    }
22}

 1async function fetchMultipleData() {
 2    try {
 3        const [data1, data2] = await Promise.all([
 4            fetch('https://codesparklab.com/json/example1.json'),
 5            fetch('https://codesparklab.com/json/example2.json')
 6        ]);
 7        const jsonData1 = await data1.json();
 8        const jsonData2 = await data2.json();
 9        console.log(jsonData1);
10        console.log(jsonData2);
11    } catch (error) {
12        console.error('Failed to fetch data:', error);
13    }
14}
15
16fetchMultipleData();

 1async function fetchFastestData() {
 2    try {
 3        const fastestResponse = await Promise.race([
 4            fetch('https://codesparklab.com/json/example1.json'),
 5            fetch('https://codesparklab.com/json/example2.json')
 6        ]);
 7        const jsonData = await fastestResponse.json();
 8        console.log('Fastest data:', jsonData);
 9    } catch (error) {
10        console.error('Fetch error:', error);
11    }
12}
13
14fetchFastestData();

 1async function fetchWithAllSettled() {
 2    const results = await Promise.allSettled([
 3        // This URL will success
 4        fetch('https://codesparklab.com/json/example1.json'),
 5        // This URL will fail
 6        fetch('https://invalid.codesparklab.com/')
 7    ]);
 8
 9    results.forEach((result, index) => {
10        if (result.status === 'fulfilled') {
11            const url = result.value.url;
12            console.log(`Request ${index + 1} succeeded:`, url);
13        } else {
14            const reason = result.reason;
15            console.warn(`Request ${index + 1} failed:`, reason);
16        }
17    });
18}
19
20fetchWithAllSettled();

 1async function fetchAnySuccessful() {
 2    try {
 3        const firstSuccessful = await Promise.any([
 4            // This URL will fail
 5            fetch('https://invalid.codesparklab.com/'),
 6            // This URL will success
 7            fetch('https://codesparklab.com/json/example1.json')
 8        ]);
 9        const jsonData = await firstSuccessful.json();
10        console.log('First successful response:', jsonData);
11    } catch (error) {
12        console.error('All fetch requests failed:', error);
13    }
14}
15
16fetchAnySuccessful();