mirror of
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32 lines
766 B
Markdown
32 lines
766 B
Markdown
# Check If Something Is An Array
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The `Array` class has a function on it called
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[`isArray()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/isArray)
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which can be used to check if something is an array.
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```javascript
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> Array.isArray('Hello, World!');
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// => false
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> Array.isArray(['One', 2, [3]]);
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// => true
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> Array.isArray({ foo: 'bar' });
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// => false
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> Array.isArray([]);
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// => true
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```
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The MDN docs provide an [example
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polyfill](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/isArray#Polyfill)
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if it is not natively available.
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```javascript
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if (!Array.isArray) {
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Array.isArray = function(arg) {
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return Object.prototype.toString.call(arg) === '[object Array]';
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};
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}
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```
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