如何按属性过滤对象数组

Question

我有一个对象数组，如下所示：

finalistsCollection = [
    { name: 'Ann' , sections: [{id: '132', name: 'someName'}, {id: '456', name: 'someName'}] },
    { name: 'Jack' , sections: [{id: '798', name: 'someName'}] },
    { name: 'Morgan', sections: [{id: '456', name: 'someName'}] },
    { name: 'Billy', sections: [{id: '132', name: 'someName'}, {id: '456', name: 'someName'}]}, 
    { name: 'Monica', sections: [{id: '798', name: 'someName'}] }
]

如何通过 id 值过滤这个数组？现在，如果sections 数组内部只有一个对象，我已经进行了过滤：

filter(directionId) {
     filteredCollection = this.finalistsCollection.filter((item) => item.sections[0].id === directionId
}

我尝试在过滤器之后使用map() 函数，但它仍然返回整个数组。

Answer 1

这个works：

let finalistsCollection = [
    { name: 'Ann' , sections: [{id: '132', name: 'someName'}, {id: '456', name: 'someName'}] },
    { name: 'Jack' , sections: [{id: '798', name: 'someName'}] },
    { name: 'Morgan', sections: [{id: '456', name: 'someName'}] },
    { name: 'Billy', sections: [{id: '132', name: 'someName'}, {id: '456', name: 'someName'}]}, 
    { name: 'Monica', sections: [{id: '798', name: 'someName'}] }
]

function filter(directionId) {
     let filteredCollection = finalistsCollection.filter((item) => {
       for (const section of item.sections) {
         if (section.id === directionId) {
           return true
         }
       }
       return false
     })
     console.log(filteredCollection)
}

filter('456')

Answer 2

希望对你有帮助

let finalistsCollection = [
  { name: 'Ann' , sections: [{id: '132', name: 'someName'}, {id: '456', name: 'someName'}] },
  { name: 'Jack' , sections: [{id: '798', name: 'someName'}] },
  { name: 'Morgan', sections: [{id: '456', name: 'someName'}] },
  { name: 'Billy', sections: [{id: '132', name: 'someName'}, {id: '456', name: 'someName'}]}, 
  { name: 'Monica', sections: [{id: '798', name: 'someName'}] }
]

function filter(directionId) {
  return finalistsCollection.filter(item =>
    item.sections.some(x => x.id === directionId)
  );
}

console.log(filter('456'));

Answer 3

你可以在这里使用一个小技巧作为条件：

sections.map(section=>section.id).includes(directionId)

    finalistsCollection = [
        { name: 'Ann' , sections: [{id: '132', name: 'someName'}, {id: '456', name: 'someName'}] },
        { name: 'Jack' , sections: [{id: '798', name: 'someName'}] },
        { name: 'Morgan', sections: [{id: '456', name: 'someName'}] },
        { name: 'Billy', sections: [{id: '132', name: 'someName'}, {id: '456', name: 'someName'}]}, 
        { name: 'Monica', sections: [{id: '798', name: 'someName'}] }
    ]



    function filter(directionId) {
         return finalistsCollection.filter((item) =>
             item.sections.map(section=>section.id).includes(directionId))
    }
    
    console.log(filter('798'))
    console.log(filter('456'))
    console.log(filter('112'))