在JavaScript中對物件陣列進行排序和分組

我知道如何進行基本的排序和分組，但這是我找不到正確邏輯的事情。

const test = [
    {name: 'a', type: '1'},
    {name: 'a', type: '2'},
    {name: 'a', type: '3'},
    {name: 'b', type: '1'},
    {name: 'b', type: '2'},
    {name: 'c', type: '3'},
    {name: 'd', type: '1'},
    {name: 'e', type: '4'},
    {name: 'e', type: '3'},
    {name: 'f', type: '1'},
    {name: 'f', type: '2'},
    {name: 'f', type: '3'},
    {name: 'g', type: '2'},
];

在我擁有的陣列之上和我想要得到的結果之下。

const clean = [
    {type: '1-2-3', names: 'a'},
    {type: '1-2', names: 'b'},
    {type: '3', names: 'c'},
    {type: '3-4', names: 'e'},
    {type: '1', names: 'd'},
];

我有一個包含許多需要分組的雙重名稱的檔案。我需要一個具有唯一組和名稱的物件。

讓我們說名字a，b，c。a 有組 1,2,3 - b 有 2,3 c 有 1,3 我們創建 3 個組，groupName '1-2-3'。, '2-3', '1-3' 并添加適合組內的名稱，因此我們沒有'雙重名稱

我希望你們明白我的意思。請幫助我使用什么登錄名進行排序/分組

uj5u.com熱心網友回復：

您可以簡單地使用reduce, 來執行分組。像這樣：

const test = [
    {name: 'a', type: '1'},
    {name: 'a', type: '2'},
    {name: 'a', type: '3'},
    {name: 'b', type: '1'},
    {name: 'b', type: '2'},
    {name: 'c', type: '3'},
    {name: 'd', type: '1'},
    {name: 'e', type: '4'},
    {name: 'e', type: '3'},
    {name: 'f', type: '1'},
    {name: 'f', type: '2'},
    {name: 'f', type: '3'},
    {name: 'g', type: '2'},
];

const response = test.sort((a, b) => {
    return a.type - b.type;
}).reduce((agg, current) => {
  if(agg[current.name]) {
    agg[current.name] = `${agg[current.name]}-${current.type}`
  } else {
    agg[current.name] = current.type;
  }
  return agg
}, {});

const groupedData = {};
Object.entries(response).forEach(([k, v]) => {
  if(groupedData[v]) {
    groupedData[v].push(k);
  } else {
    groupedData[v] = [k];
  }
})

const output = [];
Object.entries(groupedData).forEach(([k, v]) => {
  output.push({type: k, names: v})
})
console.log(output);

uj5u.com熱心網友回復：

讓我們逐步了解它。我們需要按 對專案進行分組name。我們怎么能這樣做？

我們可以有一個映射/物件，其鍵為name，值為陣列。如果name映射/物件中不存在鍵，我們可以使用陣列對其進行初始化。否則，如果是這樣，我們可以將下一個型別推送給它。

const groups_in_array = {};
for (const item of test) {
    const { name, type } = item;
    
    if (!(name in groups_in_array)) { // Group doesn't exist yet. Initialize it with an array.
        groups_in_array[name] = [type];
    } else { 
        groups_in_array[name].push(type); // Group already exists. Push the type to it.
    }
}

name接下來，我們可以創建一個包含所有鍵s的陣列，groups_in_array并使用 連接所有型別-。

const groups = [];
for (const group in groups_in_array) {
    groups.push({
        name: group,
        type: groups_in_array[group].join("-")
    });
}

把它們放在一起。

const test = [
    {name: 'a', type: '1'},
    {name: 'a', type: '2'},
    {name: 'a', type: '3'},
    {name: 'b', type: '1'},
    {name: 'b', type: '2'},
    {name: 'c', type: '3'},
    {name: 'd', type: '1'},
    {name: 'e', type: '4'},
    {name: 'e', type: '3'},
];

const groups_in_array = {};
for (const item of test) {
    const { name, type } = item;
    
    if (!(name in groups_in_array)) {
        groups_in_array[name] = [type];
    } else { 
        groups_in_array[name].push(type);
    }
}

const groups = [];
for (const group in groups_in_array) {
    groups.push({
        name: group,
        type: groups_in_array[group].join("-")
    });
}

console.log(groups);

請注意，默認情況下物件/地圖未排序（排序）。

uj5u.com熱心網友回復：

無需過度邏輯

    const test = [
    {name: 'a', type: '1'},
    {name: 'a', type: '2'},
    {name: 'a', type: '3'},
    {name: 'b', type: '1'},
    {name: 'b', type: '2'},
    {name: 'c', type: '3'},
    {name: 'd', type: '1'},
    {name: 'e', type: '4'},
    {name: 'e', type: '3'},
  ];

  const result = test
    .sort((a, b) => a.name - b.name)
    .reduce((previous, {name, type}) => {
      const group = previous.findIndex(item => item.names === name);
      if (group > -1) {
        previous[group].type  = `-${type}`;
        previous[group].type = previous[group].type.split('-').sort((a, b) => a - b).join('-')
      } else {
        previous.push({type, names: name});
      }
      return previous;
    }, []);

  console.log(result);

標籤：javascript

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