javascript - 在 typescript 中创建动态数组？

Question

我下面有一个数组。

let arr = [{_firstName: "john", _lastName: "tom", _selectedDate: "03/12/2018", _slot: "6AM to 8AM", _phoneNumber: "+19173432970", _sport: "Soccer"},
           {_firstName: "Jason", _lastName: "Deli", _selectedDate: "03/12/2018", _slot: "6AM to 8AM", _phoneNumber: "+19134592970", _sport: "Soccer"},
           {_firstName: "Shey", _lastName: "Ford", _selectedDate: "03/12/2018", _slot: "6AM to 8AM", _phoneNumber: "+191767542970", _sport: "Soccer"},
           {_firstName: "Jake", _lastName: "Hoss", _selectedDate: "03/13/2018", _slot: "6AM to 8AM", _phoneNumber: "+191723422970", _sport: "Soccer"},
           {_firstName: "Vamsee", _lastName: "Karru", _selectedDate: "03/13/2018", _slot: "6AM to 8AM", _phoneNumber: "+18767692970", _sport: "Soccer"}];

我想比较数组中的所有对象并找到相似的对象，将其放入另一个数组中。

示例:

让我们看一下上面数组中的前 3 个对象。它们三个都很相似，因为它们具有相同的选定日期、时段和运动。如果比较时所有这三个都相似，我想创建一个动态数组。最后我可以得到不同数组中所有相似的数组对象。

数组的最后两个对象与前 3 个对象不同，因为它们具有不同的日期 (selectedDate)。下面是我需要动态数组的方式。

arr1 = [{_firstName: "john", _lastName: "tom", _selectedDate: "03/12/2018", _slot: "6AM to 8AM", _phoneNumber: "+19173432970", _sport: "Soccer"},
        {_firstName: "Jason", _lastName: "Deli", _selectedDate: "03/12/2018", _slot: "6AM to 8AM", _phoneNumber: "+19145692970", _sport: "Soccer"},
        {_firstName: "Shey", _lastName: "Ford", _selectedDate: "03/12/2018", _slot: "6AM to 8AM", _phoneNumber: "+19177612370", _sport: "Soccer"}];

arr2 = [{_firstName: "Jake", _lastName: "Hoss", _selectedDate: "03/13/2018", _slot: "6AM to 8AM", _phoneNumber: "+191776639270", _sport: "Soccer"},
        {_firstName: "Vamsee", _lastName: "Karru", _selectedDate: "03/13/2018", _slot: "6AM to 8AM", _phoneNumber: "+19100692465", _sport: "Soccer"}];

有什么方法可以通过创建动态数组来实现此目的吗？

请帮忙。谢谢。

Answer 1

您可以使用函数reduce并按这些键进行分组。

let arr = [{_firstName: "john", _lastName: "tom", _selectedDate: "03/12/2018", _slot: "6AM to 8AM", _phoneNumber: "+19173432970", _sport: "Soccer"},           {_firstName: "Jason", _lastName: "Deli", _selectedDate: "03/12/2018", _slot: "6AM to 8AM", _phoneNumber: "+19177692970", _sport: "Soccer"},           {_firstName: "Shey", _lastName: "Ford", _selectedDate: "03/12/2018", _slot: "6AM to 8AM", _phoneNumber: "+19177692970", _sport: "Soccer"},           {_firstName: "Jake", _lastName: "Hoss", _selectedDate: "03/13/2018", _slot: "6AM to 8AM", _phoneNumber: "+19177692970", _sport: "Soccer"},           {_firstName: "Vamsee", _lastName: "Karru", _selectedDate: "03/13/2018", _slot: "6AM to 8AM", _phoneNumber: "+19177692970", _sport: "Soccer"}];
           
let result = arr.reduce((a, c) => {
  let groupKey = ['_selectedDate', '_slot', '_sport'].map(g => c[g]).join('|');
  (a[groupKey] || (a[groupKey] = [])).push(c);  
  return a;
}, {});

console.log(result);

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