js的几种去重方法

1、include去重

仅限数组格式，对象格式不可以

 if (!this.cTypeList.includes(element["cTypestation"])) {
                    this.cTypeList.push(element["cTypestation"]);
                }

2、set去重 建立map表

public map = new Map<number, string>()
  //初始化查询 表格数据
  refresh() {
    this.source = [];    this.VegeStatisticsEleService.getNPPQuery().subscribe(data => {
      //区域代码cCode 去重
      let set = new Set<number>();
      data.forEach(d => {
        set.add(d.cCode);
      })
      //建立map表{ key:cCode value:cName}
      set.forEach(item => {
        this.promiseArr.push(this.AreaService.getByKey(item).then(nameData => {
          this.map.set(item, nameData.cName)
        }));
      })
      console.log(this.map);
    });
  }

//思路
li.isChecked=new Set(this.listOfId).has(li.id)

3.数组去重

e//年份
let item = {
      label: this.selYear.toString(),
      pngPrnStr: this.productService.makeProductName("BEHB", "VEGE", this.selYear + this.dateArr[1] + "00000000", this.selYear + this.dateArr[0] + "00000000", this.field, this.reso, "HL", "png"),
      imgPrnStr: this.productService.makeProductName("BEHB", "VEGE", this.selYear + this.dateArr[1] + "00000000", this.selYear + this.dateArr[0] + "00000000", this.field, this.reso, "HL", "img")
    }

    this.array.forEach((d, i) => {
        if (d.label == e) {
           this.array.splice(i, 1, item)//有相同年份数据，更新该键值
        }
      })
    if (!this.array.includes(item)) {
      this.array.push(item);
    }