<el-tree
          class="tree"
          :data="nodeData"
          :props="defaultProps"    
          @node-click="handleNodeClick"
        >
  </el-tree>

data(){
return {
    nodeCount:0,
    preNodeId:null,
    curNodeId:null,
    nodeTimer:null
}
}
methods:{
    handleNodeClick(data,node,prop) {
      console.log(data,node,prop);
      this.nodeCount++
      if( this.preNodeId && this.nodeCount >= 2){
        this.curNodeId = data.id
        this.nodeCount = 0
        if(this.curNodeId == this.preNodeId){//第一次点击的节点和第二次点击的节点id相同
          console.log('双击,执行代码写在这里');
          this.curNodeId = null
          this.preNodeId = null      
          return
        }
      }
      this.preNodeId = data.id
      this.nodeTimer = setTimeout(() => { //300ms内没有第二次点击就把第一次点击的清空
        this.preNodeId  = null
        this.nodeCount = 0
      },300)  
    },
}