I defined myArr
variable in javascript
as follows:
var myArr= Array(3);
When I consoled
the value of myArr
it gave the following output:
[undefined × 3]
When I used the javascript join function which is as follows:
myArr.join('X');
And consoled
the output I got the following:
"XX"
Can somebody explain me why I got this output? I was expecting the output to be
"undefinedXundefinedX"
Array(3)
creates an array of three empty holes .
To achieve your desired result, you need to fill the holes: Array(3).fill()
Array.prototype.join will perform the string conversions of all array elements and joined into one string. If an element is undefined or null, it is converted to the empty string. join
All the undefined elements are equal to ["", "", ""].join('X')
Array(3)
will create an array of length 3.
On consoling myArr
it will log empty array
join will join all elements of the array into a string
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