106 lines
2.1 KiB
Markdown
106 lines
2.1 KiB
Markdown
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# `where()`
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The where method filters the collection by a given key / value pair:
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```js
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const collection = collect([
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{ product: 'Desk', price: 200, discounted: true },
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{ product: 'Chair', price: 100, discounted: true },
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{ product: 'Bookcase', price: 150, discounted: true },
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{ product: 'Door', price: 100 },
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]);
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const filtered = collection.where('price', 100);
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filtered.all();
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// [
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// { product: 'Chair', price: 100 },
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// { product: 'Door', price: 100 },
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// ]
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const discounted = collection.where('discounted');
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discounted.all();
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// [
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// { product: 'Desk', price: 200, discounted: true },
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// { product: 'Chair', price: 100, discounted: true },
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// { product: 'Bookcase', price: 150, discounted: true },
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// ]
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const notDiscounted = collection.where('discounted', false);
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discounted.all();
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// [
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// { product: 'Door', price: 100 },
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// ]
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```
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> When working with nested objects `where()` method allows dot notated keys. E.g. `where('product.category', 'office-supplies')`
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> The where method also allows for custom comparisons:
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**Non-identity / strict inequality `(!==)`**
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```js
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const filtered = collection.where('price', '!==', 100);
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filtered.all();
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// [
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// { product: 'Desk', price: 200 },
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// { product: 'Bookcase', price: 150 },
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// ]
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```
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**Less than operator `(<)`**
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```js
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const filtered = collection.where('price', '<', 100);
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filtered.all();
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// []
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```
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**Less than or equal operator `(<=)`**
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```js
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const filtered = collection.where('price', '<=', 100);
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filtered.all();
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// [
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// { product: 'Chair', price: 100 },
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// { product: 'Door', price: 100 },
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// ]
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```
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**Greater than operator `(>)`**
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```js
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const filtered = collection.where('price', '>', 100);
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filtered.all();
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// [
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// { product: 'Desk', price: 200} ,
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// { product: 'Bookcase', price: 150 },
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// ]
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```
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**Greater than or equal operator `(>=)`**
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```js
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const filtered = collection.where('price', '>=', 150);
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filtered.all();
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// [
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// { product: 'Desk', price: 200} ,
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// { product: 'Bookcase', price: 150 },
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// ]
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```
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[View source on GitHub](https://github.com/ecrmnn/collect.js/blob/master/src/methods/where.js)
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