el-tree 滚动条，自定义svg格式折叠、展开icon

显示滚动条

el-tree的容器元素
.tree-wrap {
  overflow: auto;
}
// 下面一行代码是关键
/deep/ .el-tree-node > .el-tree-node__children {
  overflow: visible;
}

自定义icon

.el-tree-node__expand-icon.expanded {
  -webkit-transform: rotate(0deg);
  transform: rotate(0deg);
}
.el-icon-caret-right:before {
  font-size:12px;
  // 对svg图片编码即可展示
  content: url(encodeURI('@/assets/add-icon.svg'))
}
.el-tree-node__expand-icon.expanded.el-icon-caret-right:before{
  content:url(同上)
}
is-leaf.el-icon-cart-right::before{
  content:''
}