折线图条数不定，需按后端给出数据进行相应展示，且色值不能使用默认的样式

<div id="lineEchart"></div>

getLineChart(){
  let mychart=this.$echarts.init(document.getElementById('lineEchart'))
  let seriesList=[],lengedList=[]
  let data={
    xdata:['20200301','20200302','20200303','20200304','20200305','20200306','20200307'],
    seriesData:[
      {name:'组合1',data:[20,30,21,22,25,32,30]},
      {name:'组合2',data:[24,34,44,40,36,35,29]},
      {name:'组合3',data:[50,52,41,48,37,40,45]},
      {name:'组合4',data:[36,34,30,24,28,39,38]},
      {name:'组合5',data:[46,42,37,46,41,40,35]}
    ]
  }
  let colors = ['235,100,148', '20,224,219','25,150,237','248,246,103']
  let colors2 =['#eb6494','#14e0db','#1996ed','#f8f667']
  let i=0;
  data.seriesData.forEach(item=>{
    let color = colors[i%colors.length];
    let obj={
      name: item.name,
      type: 'line',
      yAxisIndex: 0,
      data:item.data,
      color: colors2[i],
      showSymbol:false,
      areaStyle: {
        color: {
          type: 'linear',
          x: 0,
          y: 0,
          x2: 0,
          y2: 1,
          colorStops: [
            {
              offset: 0,
              color: 'rgba('+color+',0.9)'
            }, {
              offset: 1,
              color: '#fff'
            } ],
          global: false // 缺省为 false
        },
      },
    }
    seriesList.push(obj)
    lengedList.push(item.name)
    i++
  })
  const option = {
    tooltip: {
      trigger: 'axis',
    },
    legend:{
      bottom:'1%',
      data:lengedList
    },
    grid: {
      top:'8%',
      left: '3%',
      right: '4%',
      bottom: '20%',
      containLabel: true
    },
    xAxis: {
      type: 'category',
      boundaryGap: false,
      data: data.xdata,
      axisLabel: {
        // rotate: 60,  x轴文字旋转
        formatter(val) {
          if (val === 'undefined' || val === 'null') return '';
          return val
        },
      }
    },
    yAxis: [
      {
        type: 'value',
        scale:true,   //不强制包含0刻度
        axisLabel: {
          formatter: function (value) {
            return value
          }
        }
      },
    ],
    series:seriesList,
  };
  mychart.setOption(option);

},