1.安装

npm i vue2-org-tree
npm install -D less-loader less

安装 less-loader出错解决办法，直接在package.json=》devDependencies下面加入less和less-loader版本，然后执行npm i
，我用的nodejs版本是 16.18.0，“webpack”: “^4.47.0”

2.demo

<template>
  <div ref="appContainer" class="app-container">
    <div style="margin-left:30px;">
      <el-row :gutter="20">
        <el-col :span="5">
          <el-switch v-model="horizontal" :width="50" active-text="横排" inactive-text="竖排" style="margin-top:8px;"/>
        </el-col>
      </el-row>
    </div>

    <div style="font-size:12px;margin-top:30px;">
      <vue2-org-tree
        :data="treeData"
        :horizontal="!horizontal"
        collapsable
        :render-content="renderContent"
        @on-expand="onExpand"
        @on-node-click="NodeClick"/>
    </div>
  </div>
</template>


<script>
export default {
  name: "TreeTest",
  data() {
    return {
      horizontal:true,
      treeData: {
        id: '0',
        label: "NBA季后赛",
        children: [
          {
            id: '1',
            label: "西部球队",
            children: [
              {
                id: '1-1',
                label: "勇士"
              },
              {
                id: '1-2',
                label: "火箭"
              },
              {
                id: '1-3',
                label: "太阳"
              },
              {
                id: '1-4',
                label: "小牛"
              }
            ]
          },
          {
            id: '2',
            label: "东部球队",
            children: [
              {
                id: '2-1',
                label: "热火"
              },
              {
                id: '2-2',
                label: "雄鹿"
              },
              {
                id: '2-3',
                label: "骑士"
              },
              {
                id: '2-4',
                label: "凯尔特人"
              }
            ]
          }
        ]
      }
    }
  },
  created() {
    this.toggleExpand(this.treeData, true);
  },
  methods: {
    collapse(list) {
      list.forEach((child) => {
        if (child.expand) {
          child.expand = false;
        }
        child.children && this.collapse(child.children);
      });
    },
    onExpand(e, data) {
      console.log(data, 'data')
      if ("expand" in data) {
        data.expand = !data.expand;
        if (!data.expand && data.children) {
          this.collapse(data.children);
        }
      } else {
        this.$set(data, "expand", true);
      }
    },
    toggleExpand(data, val) {
      if (Array.isArray(data)) {
        data.forEach((item) => {
          this.$set(item, "expand", val);
          if (item.children) {
            this.toggleExpand(item.children, val);
          }
        });
      } else {
        this.$set(data, "expand", val);
        if (data.children) {
          this.toggleExpand(data.children, val);
        }
      }
    },
    NodeClick(e, data) {
      console.log(e)
      // e 为 event
      console.log(data)
      // 当前项的所有详情 如：id label children
    },
    renderContent(h, data) {
      return (
        <div class="treeItem">{data.label}</div>
      )
    },
  }

}
</script>

<style lang="less">
.org-tree-container {
  display: inline-block;
  padding: 15px;
  background-color: #fff;
}

.org-tree {
  // display: inline-block;
  display: table;
  text-align: center;

  &:before, &:after {
    content: '';
    display: table;
  }

  &:after {
    clear: both;
  }
}

.org-tree-node,
.org-tree-node-children {
  position: relative;
  margin: 0;
  padding: 0;
  list-style-type: none;

  &:before, &:after {
    transition: all .35s;
  }
}

.org-tree-node-label {
  position: relative;
  display: inline-block;

  .org-tree-node-label-inner {
    padding: 10px 15px;
    text-align: center;
    border-radius: 3px;
    box-shadow: 0 1px 5px rgba(0, 0, 0, .15);
  }
}

.org-tree-node-btn {
  position: absolute;
  top: 100%;
  left: 50%;
  width: 20px;
  height: 20px;
  z-index: 10;
  margin-left: -11px;
  margin-top: 9px;
  background-color: #fff;
  border: 1px solid #ccc;
  border-radius: 50%;
  box-shadow: 0 0 2px rgba(0, 0, 0, .15);
  cursor: pointer;
  transition: all .35s ease;

  &:hover {
    background-color: #e7e8e9;
    transform: scale(1.15);
  }

  &:before, &:after {
    content: '';
    position: absolute;
  }

  &:before {
    top: 50%;
    left: 4px;
    right: 4px;
    height: 0;
    border-top: 1px solid #ccc;
  }

  &:after {
    top: 4px;
    left: 50%;
    bottom: 4px;
    width: 0;
    border-left: 1px solid #ccc;
  }

  &.expanded:after {
    border: none;
  }
}

.org-tree-node {
  padding-top: 20px;
  display: table-cell;
  vertical-align: top;

  &.is-leaf, &.collapsed {
    padding-left: 10px;
    padding-right: 10px;
  }

  &:before, &:after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 50%;
    height: 19px;
  }

  &:after {
    left: 50%;
    border-left: 1px solid #ddd;
  }

  &:not(:first-child):before,
  &:not(:last-child):after {
    border-top: 1px solid #ddd;
  }

}

.collapsable .org-tree-node.collapsed {
  padding-bottom: 30px;

  .org-tree-node-label:after {
    content: '';
    position: absolute;
    top: 100%;
    left: 0;
    width: 50%;
    height: 20px;
    border-right: 1px solid #ddd;
  }
}

.org-tree > .org-tree-node {
  padding-top: 0;

  &:after {
    border-left: 0;
  }
}

.org-tree-node-children {
  padding-top: 20px;
  display: table;

  &:before {
    content: '';
    position: absolute;
    top: 0;
    left: 50%;
    width: 0;
    height: 20px;
    border-left: 1px solid #ddd;
  }

  &:after {
    content: '';
    display: table;
    clear: both;
  }
}

.horizontal {
  .org-tree-node {
    // display: flex;
    // flex-direction: row;
    // justify-content: flex-start;
    // align-items: center;
    display: table-cell;
    float: none;
    padding-top: 0;
    padding-left: 20px;

    &.is-leaf, &.collapsed {
      padding-top: 10px;
      padding-bottom: 10px;
    }

    &:before, &:after {
      width: 19px;
      height: 50%;
    }

    &:after {
      top: 50%;
      left: 0;
      border-left: 0;
    }

    &:only-child:before {
      top: 1px;
      border-bottom: 1px solid #ddd;
    }

    &:not(:first-child):before,
    &:not(:last-child):after {
      border-top: 0;
      border-left: 1px solid #ddd;
    }

    &:not(:only-child):after {
      border-top: 1px solid #ddd;
    }

    .org-tree-node-inner {
      display: table;
    }

  }

  .org-tree-node-label {
    display: table-cell;
    vertical-align: middle;
  }

  &.collapsable .org-tree-node.collapsed {
    padding-right: 30px;

    .org-tree-node-label:after {
      top: 0;
      left: 100%;
      width: 20px;
      height: 50%;
      border-right: 0;
      border-bottom: 1px solid #ddd;
    }
  }

  .org-tree-node-btn {
    top: 50%;
    left: 100%;
    margin-top: -11px;
    margin-left: 9px;
  }

  & > .org-tree-node:only-child:before {
    border-bottom: 0;
  }

  .org-tree-node-children {
    // display: flex;
    // flex-direction: column;
    // justify-content: center;
    // align-items: flex-start;
    display: table-cell;
    padding-top: 0;
    padding-left: 20px;

    &:before {
      top: 50%;
      left: 0;
      width: 20px;
      height: 0;
      border-left: 0;
      border-top: 1px solid #ddd;
    }

    &:after {
      display: none;
    }

    & > .org-tree-node {
      display: block;
    }
  }
}
</style>

3.效果

参考：
https://www.cnblogs.com/liliuyu/p/17534861.html
https://blog.csdn.net/LlanyW/article/details/127647395
https://blog.csdn.net/qq_36437172/article/details/133900466