JavaScript如何筛选数组中location字段匹配国家和地区条件的对象

实现思路 #

直接使用JS数组内置的filter方法遍历数组，对每个对象的location属性同时校验是否包含国家、地区两个关键词即可，可额外加大小写转换逻辑避免大小写不匹配的问题。

完整代码实现 #

首先定义原始数据：

const cityData = [
  {
    "population": 121321313,
    "location": "American city in the East"
  },
  {
    "population": 54646546,
    "location": "Canadian city in the East"
  },
  {
    "population": 6546467,
    "location": "American city in the West"
  },
  {
    "population": 145313,
    "location": "American city in the South"
  },
  {
    "population": 12673,
    "location": "Canadian city2 in the East"
  },
  {
    "population": 141313,
    "location": "Canadian city in the South"
  },
  {
    "population": 1264473,
    "location": "Canadian city4 in the East"
  },
  {
    "population": 12673,
    "location": "Canadian city6 in the South"
  }
];

封装筛选函数：

/**
 * 筛选符合条件的城市
 * @param {string} country 国家参数，可选值：American/Canadian
 * @param {string} region 地区参数，可选值：East/West/South
 * @returns {Array} 符合条件的城市对象数组
 */
function filterCities(country, region) {
  // 统一转小写，避免大小写导致匹配失败，不需要可删除该逻辑
  const formatCountry = country.toLowerCase();
  const formatRegion = region.toLowerCase();
  return cityData.filter(item => {
    const formatLocation = item.location.toLowerCase();
    return formatLocation.includes(formatCountry) && formatLocation.includes(formatRegion);
  })
}

测试效果 #

按照需求筛选东部的加拿大城市：

const result = filterCities('Canadian', 'East');
console.log(result);

输出结果正好是索引为1、4、6的三个对象，符合预期。

严格匹配优化（可选） #

如果需要避免关键词部分匹配的异常情况（比如location字段出现CanadianAmerican同时命中两个国家的问题），可以把location按空格拆分成单词数组后再做存在性校验：

function filterCitiesStrict(country, region) {
  const formatCountry = country.toLowerCase();
  const formatRegion = region.toLowerCase();
  return cityData.filter(item => {
    const locationWords = item.location.toLowerCase().split(/\s+/);
    return locationWords.includes(formatCountry) && locationWords.includes(formatRegion);
  })
}

内容的提问来源于stack exchange，提问作者user17527939