js代码例子

// 定义一个函数
function greet(name) {
    return `Hello, ${name}!`;
}

// 调用函数并输出结果
console.log(greet('World'));

// 使用Promise解决回调地狱
function fetchData(url) {
    return new Promise((resolve, reject) => {
        setTimeout(() => {
            resolve(`Data from ${url}`);
        }, 1000);
    });
}

fetchData('https://example.com')
    .then(data => {
        console.log(data);
        return fetchData('https://another-example.com');
    })
    .then(anotherData => {
        console.log(anotherData);
    })
    .catch(error => {
        console.error('Error:', error);
    });

// 使用async/await解决回调地狱
async function fetchAllData() {
    try {
        const data1 = await fetchData('https://example.com');
        console.log(data1);
        const data2 = await fetchData('https://another-example.com');
        console.log(data2);
    } catch (error) {
        console.error('Error:', error);
    }
}

fetchAllData();