The join task joins all elements of an array (or an array-like object) into a string.
If you have a dataset within an array and you want to join it into a single string of information, use the join task.
In this example the arr variable is ["Device1", "Device2", "Device3", "Device4"] and the separator is a comma (,).
The joinedElements variable that returns is "Device1,Device2,Device3,Device4" — all elements separated by a comma within one set of double quotation marks.
For related information, see the join API reference.