how to duplicate the array values in javascript

Question

input
var key=[ 'id', 'name', 'health', 'status', 'environment', 'serviceType' ]

I am expecting the below output(duplication of the values)

[ 'id', 'name', 'health', 'status', 'environment', 'serviceType', 'id', 'name', 'health', 'status', 'environment', 'serviceType' ]

Majed Badawi · Accepted Answer · 2021-05-13 17:35:48Z

1

Using the spread-operator:

const key = [ 'id', 'name', 'health', 'status', 'environment', 'serviceType' ]

const res = [...key, ...key];

console.log(res);

Using Array#concat:

const key = [ 'id', 'name', 'health', 'status', 'environment', 'serviceType' ]

const res = key.concat(key);

console.log(res);

answered May 13, 2021 at 17:35

Majed Badawi

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Comments

ibragim · Accepted Answer · 2021-05-13 17:37:05Z

0

Try to make with for as a solution

for(let i=0; i<key.length; i++){
   key.push(key);
}

answered May 13, 2021 at 17:37

ibragim

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