What's New in ES6 Arrays
1.
empty array
2. Convert the pseudo-array into a real array
Convert a collection of p tags to a real array
Similar to the usage of map, the transformed array is also traversed.
3. Fill array (replace all arrays with one value)
1 represents the start position, 3 represents the length from the start position to the end position
4. Traverse the related array
(there is a compatibility issue)
5. Inside the current array, copy the specified array members to other locations
0 is the starting position, 3 means reading from the third one, and 4 is the ending position.
6. Find
find will only find one that meets the conditions and output its value
findIndex will output the value that matches the conditional value
array contains 1, true
