add lastDateOfMonth

snippets/lastDateOfMonth.md

@@ -0,0 +1,18 @@
+---
+title: lastDateOfMonth
+tags: date,intermediate
+---
+
+Get last date in current month of given date. 
+- Generate new date of the next month and use day 0 to get one day before it.
+
+```js
+const lastDateOfMonth = date => {
+        return new Date(date.getFullYear(),date.getMonth()+1,0);
+}
+```
+
+```js
+//Current date is 10-10-2020
+lastDateOfMonth(new Date()); // 'Sat Oct 31 2020 00:00:00 GMT+0700'
+```