无法根据另一个对象数组过滤对象数组

Posted 2023-05-09

【中文标题】无法根据另一个对象数组过滤对象数组

【英文标题】：Unable to filter an array of object based on another array of object

【发布时间】：2021-10-24 00:54:29

【问题描述】：

我有两个对象数组，其中包含 dateTime 字符串和 count 的键值对。在arr 中，我有两个对象具有相同的dateTime 值和brr's 对象的dateTime 值中的两个。我只想过滤掉数组中的arr's 不相等的对象。

我的意思是，如果我的arr是这样的：

const arr = [
     dateTime: '2021-08-14 02:00:00', count: 1 ,
     dateTime: '2021-08-15 04:00:00', count: 1 ,
     dateTime: '2021-08-16 10:00:00', count: 1 ,
     dateTime: '2021-08-16 19:00:00', count: 1 ,
     dateTime: '2021-08-17 05:00:00', count: 1 
];

brr 是这样的：

const brr = [
     dateTime: '2021-08-16 19:00:00', count: 1 ,
     dateTime: '2021-08-17 05:00:00', count: 1 
];

我正在尝试获取这样的数组：

[
     dateTime: '2021-08-14 02:00:00', count: 1 ,
     dateTime: '2021-08-15 04:00:00', count: 1 ,
     dateTime: '2021-08-16 10:00:00', count: 1 
];

没有这样做：

const arr = [
     dateTime: '2021-08-14 02:00:00', count: 1 ,
     dateTime: '2021-08-15 04:00:00', count: 1 ,
     dateTime: '2021-08-16 10:00:00', count: 1 ,
     dateTime: '2021-08-16 19:00:00', count: 1 ,
     dateTime: '2021-08-17 05:00:00', count: 1 
];

const brr = [
     dateTime: '2021-08-16 19:00:00', count: 1 ,
     dateTime: '2021-08-17 05:00:00', count: 1 
];

const newArr = [];

for( let item of brr )  

   const filtered = arr.filter( el => 
        return el.dateTime !== item.dateTime;  
   );
   
   newArr.push( filtered );
  
;

console.log( newArr );

我在控制台中遇到了一些乱码。我在这里做错了什么？

【问题讨论】：

看看这对你有没有帮助***.com/questions/54142112/…

【参考方案1】：

试试这个：

const newArr = [];

const brrDateTimes = brr.map((el) => el.dateTime);

arr.forEach((el) => 
  if (brrDateTimes.indexOf(el.dateTime) == -1) 
    newArr.push(el)
);

【参考方案2】：

您可以获取一组不需要的 dateTime 值并过滤数组。

const
    array = [ dateTime: '2021-08-14 02:00:00', count: 1 ,  dateTime: '2021-08-15 04:00:00', count: 1 ,  dateTime: '2021-08-16 10:00:00', count: 1 ,  dateTime: '2021-08-16 19:00:00', count: 1 ,  dateTime: '2021-08-17 05:00:00', count: 1 ],
    filter = [ dateTime: '2021-08-16 19:00:00', count: 1 ,  dateTime: '2021-08-17 05:00:00', count: 1 ],
    unwanted = new Set(filter.map(( dateTime ) => dateTime)),
    result = array.filter(( dateTime ) => !unwanted.has(dateTime));

console.log(result);

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【参考方案3】：

time=brr.map(x=>x.dateTime);
arr.map(x=>!time.includes(x.dateTime))

【参考方案4】：

Array.filter 对整个数组进行操作。您不需要在循环中调用它。此外，在比较对象的相同性时，您需要比较它们的标量值。在 javascript 中，具有相同值的对象仍然不相同。

const arr = [
     dateTime: '2021-08-14 02:00:00', count: 1 ,
     dateTime: '2021-08-15 04:00:00', count: 1 ,
     dateTime: '2021-08-16 10:00:00', count: 1 ,
     dateTime: '2021-08-16 19:00:00', count: 1 ,
     dateTime: '2021-08-17 05:00:00', count: 1 
];

const brr = [
     dateTime: '2021-08-16 19:00:00', count: 1 ,
     dateTime: '2021-08-17 05:00:00', count: 1 
];

const diff = arr.filter(a => 
    return !brr.some(b => 
      return a.dateTime === b.dateTime && a.count === b.count;
    );
);

console.log(diff);