如何过滤数组中的对象？

Question

我想用单个对象检查数组内的条件。

let arr = [

  {

    name: "john",

    description: {

      height: 5.5,

      weight: 54,

    },

  },

  {

    name: "mary",

    description: {

      height: 5.8,

      weight: 65,

    },

  },

  {

    name: "smith",

    description: {

      height: 6.1,

      weight: 85,

    },

  },

];

let obj = {

  height: 5.8,

  weight: 65,

};

我想比较数组中的obj，如果它匹配一个，我想得到这个名字。对于ex来说，obj等于结婚。我想打印玛丽。这就是我尝试过的。

let result = arr.filter((item) => item.description === obj )

console.log(result.name);

Answer 1

您可以使用对象的条目构建一个过滤器，并循环访问所有条目并检查值。然后映射名称。let array = [{ name: "john", description: { height: 5.5, weight: 54 } }, { name: "mary", description: { height: 5.8, weight: 65 } }, { name: "smith", description: { height: 6.1, weight: 85 } }],    object = { height: 5.8, weight: 65 },    filters = Object.entries(object),    result = array        .filter(({ description }) => filters.every(([key, value]) => description[key] === value))        .map(({ name }) => name);console.log(result);

Answer 2

您必须将所需的键相互比较，而不是比较对象，因为对象相等性基于它们的内存地址是否相同。let arr = [  {    name: "john",    description: {      height: 5.5,      weight: 54    }  },  {    name: "mary",    description: {      height: 5.8,      weight: 65    }  },  {    name: "smith",    description: {      height: 6.1,      weight: 85    }  }];let obj = {  height: 5.8,  weight: 65};console.log(  arr.filter(item => item.description.height === obj.height && item.description.weight === obj.weight));

Answer 3

一种方法是使用 .Object.keysvar arr = [ { name: "john", description: { height: 5.5, weight: 54, }, }, { name: "mary", description: { height: 5.8, weight: 65, }, }, { name: "smith", description: { height: 6.1, weight: 85, }}];var obj = { height: 5.8, weight: 65 };var result = arr.filter(({description})=>Object.keys(description).every(k=>description[k]==obj[k])).map(({name})=>name);console.log(result);

Answer 4

您可以缩小要过滤的属性范围，如下所示  let arr = [{      name: "john",      description: {        height: 5.5,        weight: 54      }    },    {      name: "mary",      description: {        height: 5.8,        weight: 65      }    },    {      name: "smith",      description: {        height: 6.1,        weight: 85      }    }  ];  let obj = {    height: 5.8,    weight: 65  };  const filtered = arr.filter(({ description }) => description.height === obj.height && description.weight === obj.weight);  console.log(filtered)

Answer 5

筛选器筛选条件失败的根本原因是由于尝试的对象之间的比较。对象的比较可以通过使用帮助程序函数来完成。以下是工作原理：// array-filter-demo.jslet arr = [    { name: "john", description: { height: 5.5, weight: 54 } },    { name: "mary", description: { height: 5.8, weight: 65 } },    { name: "smith",description: { height: 6.1, weight: 85 } }  ]let obj = { height: 5.8, weight: 65 }// Helper function to compare objectsfunction matching(a, b) {   return ( a.height === b.height && a.weight === b.weight)}// Call the helper function inside filterconst result = arr.filter(item => (matching(item.description, obj)))console.log(result)输出：$ node array-filter-demo.js [ { name: 'mary', description: { height: 5.8, weight: 65 } } ]