Javascript如何根据创建的月份显示用户数量

Question

我想根据创建用户的月份显示用户数量。我得到以下数据作为示例:

[ 
  { name: 'user1', created: 'may' },
  { name: 'user2', created: 'may' },
  { name: 'user3', created: 'may' },
  { name: 'user4', created: 'may' },
  { name: 'user5', created: 'june' },
  { name: 'user6', created: 'june' },
  { name: 'user7', created: 'august' },
  { name: 'user8', created: 'august' },
  { name: 'user9', created: 'august' } 
]

我想要实现的是这样显示它们:

may: 4
june: 2
august: 3

我该怎么做？

Answer 1

您可以使用 reduce() 并返回对象作为结果。

var data = [{"name":"user1","created":"may"},{"name":"user2","created":"may"},{"name":"user3","created":"may"},{"name":"user4","created":"may"},{"name":"user5","created":"june"},{"name":"user6","created":"june"},{"name":"user7","created":"august"},{"name":"user8","created":"august"},{"name":"user9","created":"august"}]

var result = data.reduce(function(r, e) {
  return r[e.created] = (r[e.created] || 0) + 1, r
}, {})

console.log(result)