JS Part III

1.new Keyword execution process

 2. Built-in objects

 3. How to check documents

mdn w3c

max（）

 4.math Object maximum method （ give an example ）

  As long as you still check the documents according to your own needs , For further testing and use

5.math Absolute value and three rounding methods （ Simple memory ）

6.math Object random number method （ Simple process ）

 7.date object

date Object is a constructor, so you must use new To call create it

To get the current time, you must instantiate

 8. Date formatting code

 8. The countdown is achieved

 

 9. There are two ways to create arrays

 10. Array index method

 11. String operation method