javascript - There is a problem when printing the newly composed array. There are objects in it, but the length is empty.

Question

Array A (this.slots[0].values) is newly created in the A method,
For example:
this.slots[0].values.push(newValue)
Print after creation There is no problem in coming out:

Then use it in other methods, method B,
When printed, the array becomes:

Compared:

What is the problem? No operations were performed during this period

Answer 1

It may be a problem with this pointer, var self = this, and then try using self to do this