（稍后编辑）更正：

Question

我尝试按标记：

过滤列表

const initialState = [
     {id:1 ,name: 'Product A', image: 'pic-001.jpg', tags: ['nature', 'camping', 'outdoor']},
     {id:2 ,name: 'Product B', image: 'pic-002.jpg', tags: ['winter', 'hiking', 'camping', 'snow']},
     {id:3 ,name: 'Product C', image: 'pic-003.jpg', tags: ['vacation', 'family', 'kids', 'river', 'lake', 'fishing']}
   ]

我可以使用map和filter按名称过滤列表，我的问题是当我尝试按标签列出产品时。我是否必须在我的产品过滤器中使用foreach？还有另一种方法吗？

Answer 1

您可以创建Set个所选标记，并使用Array#some检查对象中是否至少有一个标记存在于对象中。标签列表：

＆＃13;

const initialState = [
     {id:1 ,name: 'Product A', image: 'pic-001.jpg', tags: ['nature', 'camping', 'outdoor']},
     {id:2 ,name: 'Product B', image: 'pic-002.jpg', tags: ['winter', 'hiking', 'camping', 'snow']},
     {id:3 ,name: 'Product C', image: 'pic-003.jpg', tags: ['vacation', 'family', 'kids', 'river', 'lake', 'fishing']}
];

const filterByTags = ['nature', 'family'];

const filterByTagSet = new Set(filterByTags);

const result = initialState.filter((o) => 
  o.tags.some((tag) => filterByTagSet.has(tag))
);

console.log(result);

＆＃13;

Answer 2

喜欢那个？

const filter = 'nature';
const filteredResult = initialState.filter((item) => {
    return (item.tags.indexOf(filter) >= 0);
});

Answer 3

你可以使用indexOf函数

var foo = initialState.filter(function(elm){
  return elm.tags.indexOf("camping")>=0
});

Answer 4

首先获取所有标签并从initialState过滤重复的标签。将数组保存为uniqueTags。

然后将uniqueTags与initialState名称进行比较，以创建另一个包含对象及其属性标签和产品的数组productTags。

const initialState = [
     {id:1 ,name: 'Product A', image: 'pic-001.jpg', tags: ['nature', 'camping', 'winter', 'outdoor']},
     {id:2 ,name: 'Product B', image: 'pic-002.jpg', tags: ['winter', 'hiking', 'family', 'camping', 'snow']},
     {id:3 ,name: 'Product C', image: 'pic-003.jpg', tags: ['vacation', 'family', 'kids', 'river', 'lake', 'fishing']}
   ]

   let allTags = [];
   initialState.map((t)=>t.tags).forEach((a)=>a.forEach((b)=>allTags.push(b)))
   let uniqueTags = allTags.filter((a,i,arr)=>arr.indexOf(a,i+1)===-1)


   productTags = [];
   uniqueTags.forEach((u)=>{
       initialState.forEach((t)=>{
           if(t.tags.includes(u))
            productTags.push({'tag': u, 'product':t.name});
       })
   })


   console.log(JSON.stringify(productTags));

   /*
   [
    { "tag": "nature", "product": "Product A" }, 
    { "tag": "outdoor", "product": "Product A" }, 
    { "tag": "winter", "product": "Product A" }, 
    { "tag": "winter", "product": "Product B" }, 
    { "tag": "hiking", "product": "Product B" }, 
    { "tag": "camping", "product": "Product A" }, 
    { "tag": "camping", "product": "Product B" }, 
    { "tag": "snow", "product": "Product B" }, 
    { "tag": "vacation", "product": "Product C" }, 
    { "tag": "family", "product": "Product B" }, 
    { "tag": "family", "product": "Product C" }, 
    { "tag": "kids", "product": "Product C" }, 
    { "tag": "river", "product": "Product C" }, 
    { "tag": "lake", "product": "Product C" }, 
    { "tag": "fishing", "product": "Product C" }
] */

（稍后编辑）更正：

要形成正确的对象，我已将代码更改为：

const initialState = [
     {id:1 ,name: 'Product A', image: 'pic-001.jpg', tags: ['nature', 'camping', 'winter', 'outdoor']},
     {id:2 ,name: 'Product B', image: 'pic-002.jpg', tags: ['winter', 'hiking', 'family', 'camping', 'snow']},
     {id:3 ,name: 'Product C', image: 'pic-003.jpg', tags: ['vacation', 'family', 'kids', 'river', 'lake', 'fishing']}
   ]

   let allTags = [];
   initialState.map((t)=>t.tags).forEach((a)=>a.forEach((b)=>allTags.push(b)))
   let uniqueTags = allTags.filter((a,i,arr)=>!arr.includes(a,i+1))


   productTags = [];
   uniqueTags.forEach((u)=>{
       let productName = [];
       initialState.forEach((t)=>{
           if(t.tags.includes(u))
            productName.push(t.name);
       })
       productTags.push({tag:u, products:productName}); 
   })

   console.log(JSON.stringify(productTags));

   /*
    productTags = [
        {"tag":"nature","products":["Product A"]},
        {"tag":"outdoor","products":["Product A"]},
        {"tag":"winter","products":["Product A","Product B"]},
        {"tag":"hiking","products":["Product B"]},
        {"tag":"camping","products":["Product A","Product B"]},
        {"tag":"snow","products":["Product B"]},
        {"tag":"vacation","products":["Product C"]},
        {"tag":"family","products":["Product B","Product C"]},
        {"tag":"kids","products":["Product C"]},
        {"tag":"river","products":["Product C"]},
        {"tag":"lake","products":["Product C"]},
        {"tag":"fishing","products":["Product C"]}
    ] 
    */

如何过滤对象数组中的数组？

4 个答案:

（稍后编辑）更正：