Javascript：如何过滤数组中的 object

Question

I have an array that is consisted of object which has categoryName(string) field and an array(plants).

I'd like to filter using plant name, what's the best approach?

I tried with but it only returns plants array, ignores categoryName

this.itemList.map(item => item.plants.filter(p=> p.name.toLowerCase().includes(this.searchTerm.toLowerCase())));

Structure

[

 [
    categoryName: "Heating"
    plants: Array(2)
    0: {plantId: 35, name: "Alston Oven", description: "Oven", plantCategoryId: 2, whenCreated: "1519357215942", …}
    1: {plantId: 19, name: "Gregs Oven", description: null, plantCategoryId: 2, whenCreated: "1516830724579", …}
 ]



  [
    categoryName: "Refrigeration"
    plants: Array(4)
    0: {plantId: 13, name: "Fridge 1 ", description: "Walk in fridge" …}
    1: {plantId: 5, name: "Fridge 2 Updated", description: "Description of Fridge 2" …}
    2: {plantId: 4, name: "Fridge"....} 
  ]
]

Answer 1

Use filter() on the outer array and some() on the inner plants array.

This will not filter out the specific plant(s) within the plants array but keep the whole array intact. It is not clear whether you need to filter the sub array or not

const term = this.searchTerm.toLowerCase(),
      res = this.itemList.filter(({plants}) => plants.some(({name}) => name.toLowerCase().includes(term)))

Answer 2

Try:

this.itemList.map(function(a) {
    return {
        categoryName: a.categoryName,
        plants: a.plants.filter(p => p.name.toLowerCase().includes(this.searchTerm.toLowerCase()))
}}).filter(a => a.plants.length > 0)

Answer 3

Please try this example

 const searchTerm = "Alston"; const itemList = [ { categoryName: "Heating", plants: [ { plantId: 35, name: "Alston Oven", description: "Oven", plantCategoryId: 2, whenCreated: "1519357215942", }, { plantId: 19, name: "Gregs Oven", description: null, plantCategoryId: 2, whenCreated: "1516830724579", }, ], }, { categoryName: "Refrigeration", plants: [ { plantId: 13, name: "Fridge 1 ", description: "Walk in fridge" }, { plantId: 5, name: "Fridge 2 Updated", description: "Description of Fridge 2", }, { plantId: 4, name: "Fridge" }, ], }, ]; const output = itemList.filter((item) => { return item.plants.map((entry) => entry.name.toLowerCase()).join().includes(searchTerm.toLowerCase()); }); console.dir(output, { depth: null, color: true });

See

• Array.prototype.map()
• Array.prototype.filter()
• Array.prototype.join()

Answer 4

If you just want to filter the plants arrays, you don't need to use map . Use forEach() , and then reassign the plants property with the filtered array there.

this.itemList.forEach(item => 
    item.plants = item.plants.filter(p => 
        p.name.toLowerCase().includes(this.searchTerm.toLowerCase())));