项目中要用到属性结构数据，后端返回的数据不是官方默认的数据结构：

		<el-tree
          :data="treeData"
          :filter-node-method="filterNode"
          :props="defaultProps"
          @node-click="handleNodeClick"
        ></el-tree>

这是文档默认的树形数据结构：

data: [{
          label: '一级 1',
          children: [{
            label: '二级 1-1',
            children: [{
              label: '三级 1-1-1'
            }]
          }]
        }, {
          label: '一级 2',
          children: [{
            label: '二级 2-1',
            children: [{
              label: '三级 2-1-1'
            }]
          }, {
            label: '二级 2-2',
            children: [{
              label: '三级 2-2-1'
            }]
          }]
        }
      ]

后端返回回来的：

[
            {
                "id": "1399521221730304",
                "email": "123@qq.com",
                "child": [
                    {
                        "id": "1399659790548992",
                        "email": "1234@qq.com",
                        "child": [
                            {
                                "id": "1400165901697024",
                                "email": "fj@qq.com",
                                "child": [
                                    {
                                        "id": "1400671389548544",
                                        "email": "fjj@qq.com",
                                        "child": null
                                    }
                                ]
                            }
                        ]
                    },
                    {
                        "id": "1400156697001984",
                        "email": "277@qq.com",
                        "child": null
                    }
                ]
            },
            {
                "id": "1399527282712576",
                "email": "147852@qq.com",
                "child": null
            },
          ]

直接使用数据树形结构展示不出来,可以改变默认展示的数据格式：

defaultProps: {
    children: 'child',
    label: 'email'
  },