Question

例如，我们有对象数组；

let arr = [
    {id: 10, name: 'hello10'}, 
    {id: 10, name: 'hello10'},
    {id: 13, name: 'hello13'},
    {id: 16, name: 'hello16'},
    {id: 17, name: 'hello17'},
    {id: 17, name: 'hello17'},
    {id: 17, name: 'hello17'}
];

我将创建数组映射后，如何在React中获得下面的结构？这应该是通用的，因为我们不知道我们会得到的id。

<div>
    <p>hello10</p>
    <p>hello10</p>
</div>
<div>
    <p>hello13</p>
</div>
<div>
    <p>hello16</p>
</div>
<div>
    <p>hello17</p>
    <p>hello17</p>
    <p>hello17</p>
</div>

Answer 1

首先尝试按ID对数据进行分组：

Object.values(
  arr.reduce((acc, item) => ({
    ...acc,
    [item.id]: (acc[item.id] || []).concat(item),
  }), {})
).map(group => (
  <div>
    {group.map(item => (
      <p>{item.name}</p>
    ))}
  </div>
))

Answer 2

您可以预先分组，然后使用标签呈现结果。

var array = [ { id: 10, name: 'hello10' }, { id: 10, name: 'hello10' }, { id: 13, name: 'hello13' }, { id: 16, name: 'hello16' }, { id: 17, name: 'hello17' }, { id: 17, name: 'hello17' }, { id: 17, name: 'hello17' }],
    grouped = array.reduce((r, o, i, a) => {
        if (o.id === (a[i - 1] && a[i - 1].id)) {
            r[r.length - 1].push(o);
        } else {
            r.push([o]);
        }
        return r;
    }, []);
    
console.log(grouped);

.as-console-wrapper { max-height: 100% !important; top: 0; }

Answer 3

您可以尝试

let dict = {};
let idArr = [];

const len = arr.length;

//We are grouping our data by id
arr.map((ar) =< {
    if(!dict[ar.id]){
        dict[arr[i].id] = [];
        idArr.push(arr[i].id);
    }
    dict[arr[i].id].push(arr[i]);
});

// Now we will generate the output
idArr.map((id) => {
    return <div>{dict[id].map((elem) => <p>{elem}</p>)}</div>
});

根据条件进行反应，在不同的div中渲染数组

3 个答案: