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30 lines
585 B
Markdown
30 lines
585 B
Markdown
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## 使用 Promise 封装 SetTimeout 定时器
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代码举例：
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```js
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// 方法：XX秒后执行指定的代码。这个方法，就是在宏任务（定时器）的执行过程中，创建了一个微任务（resolve）
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function delaySeconds(delay = 1000) {
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return new Promise((resolve) => setTimeout(resolve, delay));
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}
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delaySeconds(2000)
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.then(() => {
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console.log('qiangu');
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return delaySeconds(3000);
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})
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.then(() => {
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console.log('yihao');
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});
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```
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打印结果：
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```js
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// 2秒后打印：
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qiangu
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// 再等3秒后打印：
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yihao
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```
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