Question

我正在尝试创建一个功能类似于搜索机制的函数，该函数遍历对象数组并返回包含此数组中特定值（搜索参数）的特定数组对象

var jobs= [
  {
    "startDate": "5/2017",
    "endDate": null,
    "isCurrent": true,
    "seniority": "Senior",
  },
  {
    "startDate": "5/2013",
    "endDate": "5/2019",
    "isCurrent": false,
    "seniority": "Junior",
  },
]

我想创建一个函数，在其中提供数组，数组键和数组值，即

nameOfFunction(jobs,"seniority","Senior")

它返回/记录

{"startDate": "5/2017","endDate": null,"isCurrent": true,"seniority": "Senior",},

Answer 1

数组的filter方法可以做到这一点，但是如果要包装它，可以执行以下操作……

version: "3"

services:

  gradle:
    depends_on:
      - elasticsearch

  elasticsearch:
    image: elasticsearch{6/7}

Answer 2

您可以使用template <std::size_t, typename T> using always_t = T; template <typename Seq> class DiscreteFunImpl; template <std::size_t ... Is> class DiscreteFunImpl<std::index_sequence<Is...>> { private: std::function<int (always_t<Is, int>...)> f; public: DiscreteFunImpl(std::function<int (always_t<Is, int>...)> f): f(f) {} int eval(const array<int, sizeof...(Is)>& x) const { return f(x[Is]...); } }; template <std::size_t N> using DiscreteFun = DiscreteFunImpl<std::make_index_sequence<N>>;：

filter

编辑：

var jobs= [
  {
    "startDate": "5/2017",
    "endDate": null,
    "isCurrent": true,
    "seniority": "Senior",
  },
  {
    "startDate": "5/2013",
    "endDate": "5/2019",
    "isCurrent": false,
    "seniority": "Junior",
  },
]


const findObject = (obj, prop, value) => obj.filter(obj => obj[prop] === value)

console.log(findObject(jobs, 'seniority', 'Senior'))

Answer 3

您可以在传入的数组中使用filter方法。在这里，我还使用destructuring assignment从传入的v中获取当前对象的值（key）。然后，我将对象（v）的值与传递给函数的val进行比较，以查看是否应将其保留在新数组中。

请参见以下示例：

const jobs= [
  {
    "startDate": "5/2017",
    "endDate": null,
    "isCurrent": true,
    "seniority": "Senior",
  },
  {
    "startDate": "5/2013",
    "endDate": "5/2019",
    "isCurrent": false,
    "seniority": "Junior",
  },
];

const filterArr = (arr, key, val) => 
  arr.filter(({[key]:v}) => v===val);
  
console.log(filterArr(jobs, "seniority", "Senior"));

Answer 4

您可以尝试一下，

var jobs= [
  {
    "startDate": "5/2017",
    "endDate": null,
    "isCurrent": true,
    "seniority": "Senior",
  },
  {
    "startDate": "5/2013",
    "endDate": "5/2019",
    "isCurrent": false,
    "seniority": "Junior",
  },
];

// This function will return array of filtered elements
function searchArray(array,propertyKey,propertyValue){
  return array.filter(function(a){
      return a[propertyKey] === propertyValue;
  });
}

console.log(searchArray(jobs, 'seniority', 'Senior'));

// With new way

function searchArrayNewMethod(array,propertyKey,propertyValue){
  return array.filter( a => a[propertyKey] === propertyValue);
}


console.log(searchArrayNewMethod(jobs, 'seniority', 'Senior'));

从包含特定值的对象的多维数组返回数组对象

4 个答案: