JS: Array.prototype.join (to string)

xArray.join()

• Convert array to a string. Return it.
• Each array elements is converted to string.
• Comma "," separator inserted between elements.
• Nested array elements are flattened.

console.log( [3, 4, 5].join() === "3,4,5" )

console.log([1, 2, [3, [4, 6]]].join() === "1,2,3,4,6");

// example of array containing data objects
[3, { k: 4 }].join() === "3,[object Object]"

xArray.join(seperatorString)

Use seperatorString between elements.

[3, 4, 5].join("-") === "3-4-5"