64 lines
1.4 KiB
Markdown
64 lines
1.4 KiB
Markdown
---
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title: deepGet
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tags: object,intermediate
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---
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Returns the target value in a nested JSON object, based on the `keys` array.
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Compare 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.
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If the key exists in object, return target value, otherwise, return `null`.
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```js
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---
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title: deepGet
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tags: object,intermediate
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---
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Returns the target value in a nested JSON object, based on the `keys` array.
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Compare 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.
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If the key exists in object, return target value, otherwise, return `null`.
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```js
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const deepGet = (obj, keys) =>
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keys.reduce(
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(xs, x) => (xs && xs[x] !== null && xs[x] !== undefined ? xs[x] : null),
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obj
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);
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```
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```js
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let index = 2;
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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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name: null,
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isDark: false
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};
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deepGet(data, ['foo', 'foz', index]); // get 3
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deepGet(data, ['foo', 'bar', 'baz', 8, 'foz']); // undefined
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deepGet(data, ['name']); // null
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deepGet(data, ['isDark']); // false
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```
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```
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```js
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let index = 2;
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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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deepGet(data, ['foo', 'foz', index]); // get 3
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deepGet(data, ['foo', 'bar', 'baz', 8, 'foz']); // null
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```
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