在javascript中查找对象中键值对的频率

想象我有一个物体

teaherList = [
{teacherID:1,teacherName:"john"},
{teacherID:2,teacherName:"joe"},
{teacherID:3,teacherName:"jill"},
{teacherID:1,teacherName:"john"},
{teacherID:2,teacherName:"joe"},
{teacherID:3,teacherName:"jill"},
{teacherID:1,teacherName:"john"},
{teacherID:2,teacherName:"joe"},
{teacherID:3,teacherName:"jill"},
]

现在，我如何在对象teacherList中找到每个[teacherID:，teacherName:]的频率

我现在做的是,

let temp = []
_.each(teaherList, function(k){
   temp.push(k.teacherID)
)

let count1 = countBy(temp);

它给出了教师在对象中出现的频率，但有没有更好、更有效的方法来完成这项任务

let temp = []
_.each(teaherList, function(k){
   temp.push(k.teacherID)
)

let count1 = countBy(temp);
console.log(count1) // object
//(1:3,2:3,3:3)

---

请告诉我是否有更好的方法来解决这个问题，假设

teaherList

是一个对象数组，这里有一个方法不需要依赖于库，还可以使用

reduce

一次性创建输出对象（总迭代次数=数组长度）：

const teaherList=[
{teacherID:1，teacherName:“john”}，
{teacherID:2，teacherName:“joe”}，
{teacherID:3，teacherName:“吉尔”}，
{teacherID:1，teacherName:“john”}，
{teacherID:2，teacherName:“joe”}，
{teacherID:3，teacherName:“吉尔”}，
{teacherID:1，teacherName:“john”}，
{teacherID:2，teacherName:“joe”}，
{teacherID:3，teacherName:“吉尔”}，
];
console.log(
减少（（a，{teacherName}）=>(
赋值（a，{[teacherName]：（a[teacherName]| | 0）+1}）
), {})
);我稍微修改了这个teaherList，因为它不是有效的对象。您可以尝试这样的方法，结果数组将如下所示[{teacherID1:teacherName1}，{teacherID2:teacherName2}]


var teaherList=[
{teacherID:1，teacherName:“john”}，
{teacherID:2，teacherName:“joe”}，
{teacherID:3，teacherName:“吉尔”}，
{teacherID:1，teacherName:“john”}，
{teacherID:2，teacherName:“joe”}，
{teacherID:3，teacherName:“吉尔”}，
{teacherID:1，teacherName:“john”}，
{teacherID:2，teacherName:“joe”}，
{teacherID:3，teacherName:“吉尔”}，
]
var结果=teaherList.reduce（功能（acc、cV）{
如果（！acc[cV.教师姓名]）{
acc[cV.teacherName]={teacherID:cV.teacherID，
教师姓名：cV.teacherName，
计数：1}；
}否则{
acc[cV.teacherName].count++；
}
返回acc；
}, {});
控制台日志（结果）您可以在没有开销的情况下为每个循环分配对象并返回对象


var teacherList=[{teacherID:1，teacherName:“约翰”}，{teacherID:2，teacherName:“乔”}，{teacherID:3，teacherName:“吉尔”}，{teacherID:1，teacherName:“约翰”}，{teacherID:2，teacherName:“乔”}，{teacherID:3，teacherName:“吉尔”}，{teacherID:1，teacherName:“约翰”}，{teacherID:3，teacherName:“吉尔”}，
频率=Object.create（空）；
forEach（（{teacherName}）=>frequency[teacherName]=（frequency[teacherName]| | 0）+1）；
console.log（frequency）；
这里有另一种使用while循环的方法


teacherList=[{teacherID:1，teacherName:“约翰”}，{teacherID:2，teacherName:“乔”}，{teacherID:3，teacherName:“吉尔”}，{teacherID:1，teacherName:“约翰”}，{teacherID:2，teacherName:“乔”}，{teacherID:3，teacherName:“吉尔”}，{teacherID:1，teacherID:“约翰”}，{；
const calculateFrequencies=（{input，output=Object.create（null），id，name，
开始：i=0，结束=input.length}）=>{
而（iconsole.log（calculateFrequencies（{input:teacherList}））；
这是
teacherList
对象有效吗？正确吗？是的，这是一个有效的对象我很确定你的意思是要有一个对象数组，例如
{teacherID:1，teacherName:“john”}，
-你现在的语法无效。你说得对{teacherID:1，teacherName:“john”}这是有效的语法，我的朋友，代码只是将键绑定到它的值，所需的输出类似于[{teacherID:1 teacherName:“john”，count:3}，{teacherID:2 teacherName:“Joe”，count:3}，{teacherID:3 teacherName:“jill”，count:3}]@Navenkariyappa得到了！！我会尝试得到它。