Javascript 数组格式化 - 重复数据

Question

我想在下面的员工数组中将重复的建筑物名称显示为一个数组。

const employess = [
  {
    building_name: "A",
    name: "John"
  },
  {
    building_name: "B",
    name: "John"
  },
  {
    building_name: "A",
    name: "Doe"
  },
  {
    building_name: "c",
    name: "John"
  },
  {
    building_name: "B",
    name: "Doe"
  }, 
  {
    building_name: "C",
    name: "David"
  }
];

比如我要转换成下面的数组格式

const employess = [
  {
    building_name: ["A", "B", "C"],
    name: "John"
  },
  {
    building_name: ["A", "B"],
    name: "Doe"
  },
  {
    building_name: ["C"],
    name: "David"
  }
]

非常感谢您的帮助。

Answer 1

取自

const employess = [{
    building_name: "A",
    name: "John"
  },
  {
    building_name: "B",
    name: "John"
  },
  {
    building_name: "A",
    name: "Doe"
  },
  {
    building_name: "c",
    name: "John"
  },
  {
    building_name: "B",
    name: "Doe"
  },
  {
    building_name: "C",
    name: "David"
  }
]

let output = []

employess.forEach(function(item) {
  var existing = output.filter(function(v, i) {
    return v.name == item.name;
  });
  if (existing.length) {
    var existingIndex = output.indexOf(existing[0]);
    output[existingIndex].building_name = output[existingIndex].building_name.concat(item.building_name);
  } else {
    if (typeof item.building_name == 'string')
      item.building_name = [item.building_name];
    output.push(item);
  }
});

console.log(output)

Javascript 数组格式化 - 重复数据

Javascript Array Formatting - Repeating Data

javascript

arrays

formatting

object