如何将相同属性的数组对象合并并统计个数？

回答4

• 
  @fukeyou

  data.reduce((obj, item) => {  
    let find = obj.find(i => i.id === item.id)  
    let _d = {  
      ...item,  
      count: 1  
    }  
    find ? find.count++ : obj.push(_d)  
    return obj  
  }, [])

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  2021-11-27 07:13

• 
  
  @wang124

    let dataArr = [你的那个数组]
    let result = {};
    for (let i = 0, len = dataArr.length; i < len; i++) {
      let data = dataArr[i];
      if (result[data.id]) {
        result[data.id]["count"] += 1;
      } else {
        result[data.id] = { ...data, count: 1 };
      }
    }
    let resultArr = [];
    for (const key in result) {
      resultArr.push(result[key]);
    }
    

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  2021-11-27 07:33

• 
  
  @fei1024

  Object.entries(data.reduce((a,c)=>{
    if(!a[c.id]){
      a[c.id] = {
          ...c,
          count:1
      }
    }else{
      a[c.id].count += 1;
    }
    return a;
  },{})).map(entry=>entry[1])

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  2021-11-27 08:47

• 
  
  @cjmkt

  // 1th Method
  var interimArray = [];   // 用来存放去重后的id的
  var resultArray = [];   // 最终的期望结果
  
  var count = 1;
  for (var i in data) {
    if (interimArray.indexOf(data[i].id) > -1) {
      console.log(`${data[i].id}已经存在，计数加1`, `count为${count}`);
      for (var j in resultArray) {
        if (resultArray[j].id === data[i].id) {
          count++;
          resultArray[j].count = count;
        }
      }
    } else {
      count = 1;
      console.log(`${data[i].id}不存在，数组加入${data[i].id}`, `count重置为${count}`);
      interimArray.push(data[i].id);
      data[i].count = count;
      resultArray.push(data[i]);
    }
  }
  
  console.log(JSON.stringify(resultArray, null, 2));

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  2021-11-27 09:43