24 lines
551 B
Markdown
24 lines
551 B
Markdown
---
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title: getMonthDays
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tags: date,intermediate
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---
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Get the number of days in the month according to the specified month.
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- Use `new Date(year, monthIndex, day)`, set the parameter day to `0` to get last day of the month.
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- Use `Date.prototype.getDate` to get the day of month.
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```js
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const getMonthDays = (year, month) => {
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const today = new Date();
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return new Date(year || today.getFullYear(), month || (today.getMonth() + 1), 0).getDate();
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};
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```
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```js
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getMonthDays(); // 30
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getMonthDays(2020, 2); // 29
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getMonthDays(2021, 2); // 28
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```
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