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JSON Array Litterals

This is a JSON string:

'["Ford", "BMW", "Fiat"]'

Inside the JSON string there is a JSON array literal:

["Ford", "BMW", "Fiat"]

Arrays in JSON are almost the same as arrays in JavaScript.

In JSON, array values must be of type string, number, object, array, boolean or null.

In JavaScript, array values can be all of the above, plus any other valid JavaScript expression, including functions, dates, and undefined.


JavaScript Arrays

You can create a JavaScript array from a literal:

Example

myArray = ["Ford", "BMW", "Fiat"];
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You can create a JavaScript array by parsing a JSON string:

Example

myJSON = '["Ford", "BMW", "Fiat"]';
myArray = JSON.Parse(myJSON);
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Accessing Array Values

You access array values by index:

Example

myArray[0];
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Arrays in Objects

Objects can contain arrays:

Example

{
"name":"John",
"age":30,
"cars":["Ford", "BMW", "Fiat"]
}

You access array values by index:

Example

myObj.cars[0];
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Looping Through an Array

You can access array values by using a for in loop:

Example

for (let i in myObj.cars) {
  x += myObj.cars[i];
}
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Or you can use a for loop:

Example

for (let i = 0; i < myObj.cars.length; i++) {
  x += myObj.cars[i];
}
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