Question

似乎_.reduce（或等效的本机函数）的示例非常简单。有人可以提供一个使用此函数求和然后对对象数组进行排序/排序的示例吗？例如，如果我的数组包含 -

[{ name: 'John', store: 23,  revenue: 300.00 }, 
{ name: 'John', store: 23,  revenue: 600.00 },
{ name: 'Kerry', store: 23,  revenue: 100.00 },
{ name: 'Kerry', store: 23,  revenue: 200.00 },
{ name: 'Lars', store: 24,  revenue: 600.00 },
{ name: 'Lars', store: 24,  revenue: 800.00 },
{ name: 'Lars', store: 24,  revenue: 1000.00 },
{ name: 'Indira', store: 24,  revenue: 1800.00 },
{ name: 'Indira', store: 24,  revenue: 2800.00 },
{ name: 'Indira', store: 24,  revenue: 3800.00 },
{ name: 'Jacinta', store: 24,  revenue: 300.00 }]

我希望输出如下：

[{store: 23, rank: 1, name: 'John', revenue: 900.00},
{store: 23, rank: 2, name: 'Kerry', revenue: 300.00},
{store: 24, rank: 1, name: 'Indira', revenue: 8400.00},
{store: 24, rank: 2, name: 'Lars', revenue: 2400.00},
{store: 24, rank: 3, name: 'Jacinta', revenue: 300.00}]

最好的方法是什么？

Answer 1

这个小怪物似乎在做这个工作：

result = _(data).chain().groupBy('name').map(function(g) {
    return {
        name:g[0].name,
        store:g[0].store,
        revenue: _.reduce(g, function(a, b) { return a + b.revenue}, 0)
    }
}).sortBy('revenue').reverse().groupBy('store').map(function(g) {
    return _(g).chain().map(function(x, n) {
        return x.rank = n + 1, x;
    }).value()
}).values().flatten().value()

如何使用_.reduce或native reduce来对对象进行求和和排序？

1 个答案: