25 lines
676 B
Markdown
25 lines
676 B
Markdown
### deepGetter
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Returns the target value in a nested JSON object, based on the keys array.
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Contrust the keys you want in the nested JSON object as an `Array`.
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Use `Array.prototype.reduce()` to get value from nested JSON object one by one. if the key exists in object, return target value, otherwise, return null.
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```js
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const deepGetter = (obj, keys) => keys.reduce((xs, x) => (xs && xs[x]) ? xs[x] : null, obj)
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```
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```js
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let idx = 2; // or variable from other places
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const data = {
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foo: {
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foz: [1, 2, 3],
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bar: {
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baz: ['a', 'b', 'c']
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}
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}
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};
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deepGetter(data, ['foo', 'foz', idx]); // get 3
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deepGetter(data, ['foo', 'bar', 'baz', 8, 'foz']); // null
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```
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