如何补全年度销量对象数组的缺失品牌以实现对比图表绘制

问题背景 #

要绘制品牌年度销量对比图表，但现有2020年（last_year）和2021年（current_year）的销量数组存在品牌缺失，导致图表无法正常绘制。需补全两个数组中的缺失品牌，缺失品牌的total设为0，年份对应正确。

原始数据 #

var current_year = [
  {
    total: 12941.17,
    comapanyName: "Samsung",
    year: "2021"
  },
  {
    total: 17946.87,
    comapanyName: "Haier",
    year: "2021"
  },
  {
    total: 3832.36,
    comapanyName: "Beetel",
    year: "2021"
  },
  {
    total: 12528,
    comapanyName: "Celkon",
    year: "2021"
  }
];
var last_year = [
  {
    total: 427805.51,
    comapanyName: "Samsung",
    year: "2020"
  },
  {
    total: 77576.33,
    comapanyName: "Godrej",
    year: "2020"
  },
  {
    total: 53389.02,
    comapanyName: "Beetel",
    year: "2020"
  },
  {
    total: 100748.49,
    comapanyName: "Celkon",
    year: "2020"
  },
  {
    total: 4534.19,
    comapanyName: "FORD",
    year: "2020"
  },
  {
    total: 5.05,
    comapanyName: "Voltas",
    year: "2020"
  }
];

补全方案 #

按照要求执行以下两个补全操作：

• 给current_year添加last_year中存在但current_year缺失的FORD，total设为0，年份为2021
• 给last_year添加current_year中存在但last_year缺失的Haier，total设为0，年份为2020

补全后的数据 #

// 补全后的2021年数据
var current_year = [
  {
    total: 12941.17,
    comapanyName: "Samsung",
    year: "2021"
  },
  {
    total: 17946.87,
    comapanyName: "Haier",
    year: "2021"
  },
  {
    total: 3832.36,
    comapanyName: "Beetel",
    year: "2021"
  },
  {
    total: 12528,
    comapanyName: "Celkon",
    year: "2021"
  },
  {
    total: 0,
    comapanyName: 'FORD',
    year: '2021'
  }
];

// 补全后的2020年数据
var last_year = [
  {
    total: 427805.51,
    comapanyName: "Samsung",
    year: "2020"
  },
  {
    total: 77576.33,
    comapanyName: "Godrej",
    year: "2020"
  },
  {
    total: 53389.02,
    comapanyName: "Beetel",
    year: "2020"
  },
  {
    total: 100748.49,
    comapanyName: "Celkon",
    year: "2020"
  },
  {
    total: 4534.19,
    comapanyName: "FORD",
    year: "2020"
  },
  {
    total: 5.05,
    comapanyName: "Voltas",
    year: "2020"
  },
  {
    total: 0,
    comapanyName: "Haier",
    year: "2020"
  }
];

通用补全逻辑（可选） #

如果后续有更多品牌增减，可通过通用函数自动补全，避免手动操作：

// 获取数组中所有品牌名称
function getBrandNames(arr) {
  return arr.map(item => item.comapanyName);
}

// 补全数组缺失品牌
function completeMissingBrands(targetArr, sourceArr, targetYear) {
  const targetBrands = getBrandNames(targetArr);
  sourceArr.forEach(item => {
    if (!targetBrands.includes(item.comapanyName)) {
      targetArr.push({
        total: 0,
        comapanyName: item.comapanyName,
        year: targetYear
      });
    }
  });
}

// 执行补全
completeMissingBrands(current_year, last_year, "2021");
completeMissingBrands(last_year, current_year, "2020");

内容的提问来源于stack exchange，提问作者Omkarok