javascript - 计算数组中对象中两个键的出现次数

Question

我有以下包含对象的数组，并使用以下代码创建带有键“id”的计数:

var arr=[
{ id: 123, 
  title: "name1",
  status: "FAILED"
},
{
 id: 123,
 title: "name1", 
 status: "PASSED"
},
{
 id: 123,
 title: "name1",
 status: "PASSED"
},
{
 id: 123,
 title: "name1",
 status: "PASSED"
},
{
 id: 1234,
 title: "name2",
 status: "FAILED"
},
{
 id: 1234,
 title: "name2",
 status: "PASSED"
}

];


const test =arr.reduce((tally, item) => {
				
			  if (!tally[item.id]) {
				tally[item.id] = 1;
			  } else {
				tally[item.id] = tally[item.id] + 1;
			  }
			  return tally;
			}, {});
      
console.log(test);

现在我想做的是修改计数以考虑关键状态，因此结果将类似于:

[
{id:123, status:"PASSED", tally:3},
{id:123, status:"FAILED", tally:1},
{id:1234, status:"PASSED", tally:1},
{id:1234, status:"FAILED", tally:1}
]

有什么想法吗？谢谢!

Answer 1

把key做成item.id + item.status，然后就是简单的赋值

const res = Object.values(arr.reduce((a, b) => {
  a[b.id + b.status] = Object.assign(b, {tally: (a[b.id + b.status] || {tally: 0}).tally + 1});
  return a;
}, {}));

console.log(res);

<script>
const arr=[
  { id: 123,
    title: "name1",
    status: "FAILED"
  },
  {
    id: 123,
    title: "name1",
    status: "PASSED"
  },
  {
    id: 123,
    title: "name1",
    status: "PASSED"
  },
  {
    id: 123,
    title: "name1",
    status: "PASSED"
  },
  {
    id: 1234,
    title: "name2",
    status: "FAILED"
  },
  {
    id: 1234,
    title: "name2",
    status: "PASSED"
  }

];
</script>