golang--gorm无限级分类初始化

type Category struct {  BaseModel // 主键时间戳等  Name        string `gorm:"type:varchar(20);not null"`  IsDirectory bool   `gorm:"default:false" json:"is_directory" form:"is_directory"`  ParentID    int32  `json:"parent_id"`  Level       int32  `gorm:"type:int unsigned;not null;default:1"`  Path        string `gorm:"type:varchar(40);not null;default:'-'"`}

//BeforeCreate 钩子函数，用于创建分类之前初始化level和pathfunc (c *Category) BeforeCreate(tx *gorm.DB) (err error) {  if c.ParentID == 0 {    c.Level = 1    c.Path = "-"  } else {    c.Level = c.Parent().Level + 1    c.Path = c.Parent().Path + strconv.Itoa(int(c.ParentID)) + "-"  }  return}

func (c *Category) Parent() *Category {  var category Category  global.MT_DB.Find(&category, c.ParentID)  return &category}