Question

我有这两个数组：

const data = [ 
  { type: 'type1', location: 23 },
  { type: 'type2', location: 37 },
  { type: 'type3', location: 61 },
  { type: 'type4', location: 67 } 
]

const com = [ 
  { name: "com1", location: 36 },
  { name: "com2", location: 60 } 
]

我想测试数组locationComment +1中的com是否等于数组locationMethod中的data，如果是，那么我想拥有像这样的东西：

const array = [
 {type: 'type2', name: "com1"},
 {type: 'type3', name: "com2"}
]

这是我的代码：

const result = data.map((x)=>{
  const arr = [];
  com.map((y)=>{
    if(x.location == y.location+1){
      arr.push({
        type: x.type,
        name: y.name,
        location: x.location
      })
    }
  })
  return arr;
});

这是我得到的输出：

[ [],
  [ { type: 'type2', name: 'com1', location: 37 } ],
  [ { type: 'type3', name: 'com2', location: 61 } ],
  [] ]

Answer 1

由于不确定com数组中的每个元素是否都匹配，因此应使用reduce：

const data = [ 
  { type: 'type1', location: 23 },
  { type: 'type2', location: 37 },
  { type: 'type3', location: 61 },
  { type: 'type4', location: 67 } 
];

const com = [ 
  { name: "com1", location: 36 },
  { name: "com2", location: 60 } 
];

const output = com.reduce((a, { name, location }) => {
  const found = data.find(item => item.location === location + 1);
  if (found) {
    a.push({ type: found.type, name });
  }
  return a;
}, []);
console.log(output);

如果location是唯一的，则可以通过将O(N)首先转换为data索引的对象来将时间复杂度降低到location：

const data = [ 
  { type: 'type1', location: 23 },
  { type: 'type2', location: 37 },
  { type: 'type3', location: 61 },
  { type: 'type4', location: 67 } 
];

const com = [ 
  { name: "com1", location: 36 },
  { name: "com2", location: 60 } 
];

const dataByLoc = data.reduce((a, item) => {
  a[item.location] = item;
  return a;
}, {});

const output = com.reduce((a, { name, location }) => {
  const found = dataByLoc[location + 1];
  if (found) {
    a.push({ type: found.type, name });
  }
  return a;
}, []);
console.log(output);

Answer 2

如果单行解决方案不适合您，则下面的代码也应该结合使用.map（）和.find（）来工作。

const data = [ 
  { type: 'type1', location: 23 },
  { type: 'type2', location: 37 },
  { type: 'type3', location: 61 },
  { type: 'type4', location: 67 } 
]

const com = [ 
  { name: "com1", location: 36 },
  { name: "com2", location: 60 } 
]

// Final Array Output with merged properties
let finalArr = []

data.forEach(locationMethodObj => {

// Fetching the type
let finalObj = {
type: locationMethodObj.type
}

// Checking if a location match exists 
const foundObj = com.find(locationCommentObj => (locationCommentObj.location + 1) === 
locationMethodObj.location 
)

// If a match is found, then append name and push
if(foundObj){
finalObj.name = foundObj.name
finalArr.push(finalObj)
}
})

console.log(finalArr)

比较对象值并返回新数组

2 个答案: