將具有相同價值的每個對象過濾爲單個數組

Question

我只是直截了當地去追逐。

比方說，我有對象的簡單數組，其中一些對象的日期是相等的：

[{value: 67, date: 91}, {value: 48, date: 91}, {value: 15, date: 92}, {value: 77, date: 92}, {value: 10, date: 93}, {value: 5, date: 93}] 

如何過濾陣列，使具有相同日期的對象在自己的各個陣列這樣的回報：

[{value: 67, date: 91}, {value: 48, date: 91}] 
[{value: 15, date: 92}, {value: 77, date: 92}] 
[{value: 10, date: 93}, {value: 5, date: 93}] 

Answer 1

如何使用array.reduce()

var array = [{value: 67, date: 91}, {value: 48, date: 91}, {value: 15, date: 92}, {value: 77, date: 92}, {value: 10, date: 93}, {value: 5, date: 93}]; 
 
filteredArray = array.reduce((pre,curr)=> { 
 
    // check if the object has unqiue date as key 
 
    if(!pre.hasOwnProperty(curr['date'])){ 
 
     // if not, create an array with the unique date as key 
 
     pre[curr['date']] = []; 
 
    } 
 
    //push current value to array based on date 
 
    pre[curr['date']].push(curr); 
 
    // return the object 
 
    return pre; 
 
}, {}); 
 
console.log(filteredArray); 
 
console.log(Object.keys(filteredArray)); 
 
var asArray = Object.keys(filteredArray).reduce((pre,curr)=>{pre.push(filteredArray[curr]); return pre},[]) 
 
console.log(asArray);

對於票據，參考意見。

編輯：

這樣，您就可以輕鬆獲得獨特的日期。通過這樣做Object.keys(filteredArray)或只是做asArray = Object.keys(filteredArray).reduce(e)=>{prev.push(filteredArray[e]); return pre},[]}

Answer 2

var items = [{value: 67, date: 91}, {value: 67, date: 91}, {value: 67, date: 92}, {value: 67, date: 92}, {value: 67, date: 93}, {value: 67, date: 93}]; 
 

 
var storage = {}; 
 
items.map((item) => { 
 
    storage[JSON.stringify(item)] = true; 
 
}) 
 
    
 
for(element in storage) { 
 
    console.log(JSON.parse(element)); 
 
}

瞭解這個編碼A小的考慮，是必須訂購的每個對象上的元素，否則將要下降，例如，如果你有：

{ value: 67, date: 91 } 
{ date: 91, value: 67 } 

兩者都是使用上面的代碼不同的元素。

Answer 3

提取陣列可以使用for..of，in運營商，以檢查是否date是一個對象的屬性如果爲真，在這個屬性添加value，date對象到對象的數組

let arr = [{value: 67, date: 91} 
 
      , {value: 67, date: 91} 
 
      , {value: 67, date: 92} 
 
      , {value: 67, date: 92} 
 
      , {value: 67, date: 93} 
 
      , {value: 67, date: 93} 
 
      ]; 
 

 
let res = {}; 
 

 
for (let {value, date} of arr) { 
 
    if (!(date in res)) res[date] = Array({value,date}) 
 
    else res[date] = [...res[date], {value, date}] 
 
} 
 

 
console.log(res);