In Java, it is difficult to do easily with List.add
, List.remove
, and List.addAll
with JavaScript, so I tried to summarize frequently used array operations.
Add element ʻitem to array ʻarray
. In Java, List.add ()
. This operation modifies ʻarray` itself.
array.push(item)
Delete the element ʻitem in the array ʻarray
. In Java, List.remove (item)
. This operation modifies ʻarray` itself.
const index = array.indexOf(item)
if (index >= 0) {
array.splice(index, 1)
}
Add element ʻitem to ** beginning ** of array ʻarray
. In Java, List.add (0, item)
. This operation modifies ʻarray` itself.
array.unshift(item)
Add the array b
to the array ʻa. In Java,
List.addAll (b). This operation modifies ʻa
itself.
a.splice(a.length, 0, ...b)
Create an array c
by adding the array b
to the array ʻa. ʻA
itself ** does not change **.
c = a.concat(b)
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