如何在 javascript 中按类型对数组分组进行排序？

Question

I'm having a problem with sorting an object.

Lets say my array looks like this:

[{name:'a', type: 'letter', date:'30897887', active: true},
{name:'b', type: 'letter', date:'30897888', active: true},
{name:'c', type: 'number', date:'30897889', active: true},
{name:'d', type: 'letter', date:'30897890', active: false},
{name:'e', type: 'letter', date:'30897895', active: true},
{name:'f', type: 'number', date:'30897878', active: false},
{name:'g', type: 'letter', date:'30897823', active: true},
{name:'h', type: 'idk', date:'30897885456', active: true}]

I need to show the active and the not active ones by toggling the view, in this I've been successful.
What's driving me insane is: I need to group them by type with a specific order. I cannot wrap my head around a method.
Let's say the order should be "all the objects with type = number first, then idk, and letter at the end.".
How can i do it?

Answer 1

It isn't so elegant but here is an example if it can help you:

const array = [{name:'a', type: 'letter', date:'30897887', active: true},
{name:'b', type: 'letter', date:'30897888', active: true},
{name:'c', type: 'number', date:'30897889', active: true},
{name:'d', type: 'letter', date:'30897890', active: false},
{name:'e', type: 'letter', date:'30897895', active: true},
{name:'f', type: 'number', date:'30897878', active: false},
{name:'g', type: 'letter', date:'30897823', active: true},
{name:'h', type: 'idk', date:'30897885456', active: true}];

const types = ['idk', 'letter', 'number'];

let newArray = [];

types.forEach(type => {
  array.forEach(item => {
    if (item.type === type) {
      newArray = [...newArray, item];
    }
  })
});

Answer 2

You can use priority mapping and then sort the array using that map like below:

let priority = {
  "letter": 1,
  "idk": 2,
  "number": 3
};

arr.sort((a, b) => priority[a.type] - priority[b.type])

 const arr = [{ name: 'a', type: 'letter', date: '30897887', active: true }, { name: 'b', type: 'letter', date: '30897888', active: true }, { name: 'c', type: 'number', date: '30897889', active: true }, { name: 'd', type: 'letter', date: '30897890', active: false }, { name: 'e', type: 'letter', date: '30897895', active: true }, { name: 'f', type: 'number', date: '30897878', active: false }, { name: 'g', type: 'letter', date: '30897823', active: true }, { name: 'h', type: 'idk', date: '30897885456', active: true } ] let priority = { "letter": 1, "idk": 2, "number": 3 }; arr.sort((a, b) => priority[a.type] - priority[b.type]) console.log(arr) priority = { "letter": 3, "idk": 2, "number": 1 }; arr.sort((a, b) => priority[a.type] - priority[b.type]) console.log(arr)

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Answer 3

function customSort(arr, order) {
  var result = [];
  order.forEach((type) => {
      result = [...result,...arr.filter((data) => data.type === type)]
    });
  return result
}

Use it like

customSort(data, ["letter", "number", "string"])

Answer 4

You can use compare function to define custom sorting order

Try this:

 var items = [ {name:'a', type: 'letter', date:'30897887', active: true}, {name:'b', type: 'letter', date:'30897888', active: true}, {name:'c', type: 'number', date:'30897889', active: true}, {name:'d', type: 'letter', date:'30897890', active: false}, {name:'e', type: 'letter', date:'30897895', active: true}, {name:'f', type: 'number', date:'30897878', active: false}, {name:'g', type: 'letter', date:'30897823', active: true}, {name:'h', type: 'idk', date:'30897885456', active: true} ]; items.sort((item1,item2)=>{ if(item1.type === 'number'){ return -1; } if(item2.type === 'number'){ return 1; } if(item1.type === 'idk'){ return -2; } if(item2.type === 'idk'){ return 2; } }); console.log(items);