在 JavaScript 中过滤对象数组
本文将教你如何使用 JavaScript filter()
函数过滤数组中的元素。
使用数组时,最典型的工作之一是构建一个包含原始数组成员子集的新集合。假设你有多个学生对象,每个对象都有两个属性:sports
和 subjects
。
const students = [
{ sports: ["cricket", "football"], subjects: "Science" },
{ sports: ["Badminton", "Hockey"], subjects: "Math" },
{ sports: ["Chess", "cricket"], subjects: "Computer Science" },
{ sports: ["Judo", "football"], subjects: "Social Science" },
];
要找到最喜欢的运动是板球的学生,你必须像这样过滤包含 cricket
的运动:
const Cricket = students.filter((e) => e.sports.includes("cricket"));
console.log(Cricket);
输出:
[{
name: "Johnny",
sports: ["cricket", "football"]
}, {
name: "Dev",
sports: ["Chess", "cricket"]
}]
在这个例子中,我们使用了 students
数组对象的 filter()
方法并传递了一个测试每个成员的程序。在函数中,我们确定数组中每个学生的运动是否对应于 cricket
。
如果是这种情况,函数返回 true
;否则,它返回 false
。filter()
方法仅包含返回数组中传递回调函数条件的那些元素。
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