Google Earth engine -- how to get the information you want in the string through the return value of the function

The main purpose of this experiment is , Use our experimental content slice Function to cut the string , Then extract the desired information , The part of this experiment is to cut out the information in the string list , Obtain the image time information in the data , In the future, you can pass this experiment , Extend to other strings you want to cut .

The function used ：

slice(start, end, step)
Returns the starting index from the list （ Include ） To end index （ barring ） Part between .start or end The negative value of is counted backwards from the end of the list . A value larger than the size of the list is legal , But it will be truncated to the size of the list .

Parameters .
this:list ( list )
start ( Integers )
end (Integer, default: null)
step (Integer, default: null)
return . list

map(baseAlgorithm, dropNulls)
Map an algorithm in a list . The algorithm is expected to receive an object and return an object .

Parameters .
this:list ( list )
baseAlgorithm ( Algorithm )
dropNulls ( Boolean value , Default ：false).
If true, The mapped algorithm is allowed to return null , And elements that return null values will be discarded .

return . list

Code ：