求数组对象的交集，并集，补集

求数组对象的交集，并集，补集

var a=[ {id:'001',name:'product01'}, {id:'002',name:'product02'}, {id:'003',name:'product03'}, {id:'004',name:'product04'}, {id:'005',name:'product05'} ];
var b=[ {id:'003',name:'product03'}, {id:'006',name:'product06'}, {id:'007',name:'product07'}, {id:'008',name:'product08'}, ];

求交集

  let intersectionData=[]
  
     a.map((val) => {
        b.filter((item) => {
          if (
            item.id === val.id 
          ) {
            data.push(item);
          }
        });
      });
      
      console.log(intersectionData)

第二种方法在掘金的文章下改进的

      var obj = {};
      var arr = a.concat(b);

      arr.filter((item) => {
        obj.hasOwnProperty(item.id) ? intersectionData.push(item) : (obj[item.id] = true);
      });
     console.log(intersectionData)

求并集

求并集就是两个数组对象合并

 let tempArr  = [].concat(a, b);
 
 let unionData=setDuplicateRemoval(tempArr)
 
 
 
   //数组对象去重
    setDuplicateRemoval(data) {
      let result = [];
      let obj = {};
      for (let i = 0; i < data.length; i++) {
        if (!obj[data[i].id]) {
          result.push(data[i]);
          obj[data[i].id] = true;
        }
      }
      return result;
    },
  },
  console.log（unionData）

补集

    let complementData=[]

          tempArr.filter((v) => {
              //如果子集每一个都没有与父集对应的indexId就会返回false 不回添加到参数里面代表已经有的且重复的不回添加进来
              if (intersectionData.every((item) => item.indexId !== v.indexId)) {
                complementData.push(v)
              }
         });Ï
    console.log(complementData)