Name

Array.join() — concatenate array elements to form a string

Synopsis

array.join()
array.join(separator)

Arguments

separator

An optional character or string used to separate one element of the array from the next in the returned string. If this argument is omitted, a comma is used.

Returns

The string that results from converting each element of array to a string and then concatenating them together, with the separator string between elements.

Description

join() converts each element of an array to a string and then concatenates those strings, inserting the specified separator string between the elements. It returns the resulting string.

You can perform a conversion in the opposite direction—splitting a string into array elements—with the split() method of the String object. See String.split() for details.

Example

a = new Array(1, 2, 3, "testing");
s = a.join("+");  // s is the string "1+2+3+testing"

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