golang gorp插入恐慌

Question

Hi I'm using gorp and mysql. when insert struct gorp return

reflect.Value.Interface: cannot return value obtained from unexported field or method

In gorp docs says Panics if any interface in the list has not been registered with AddTablebut I added this struct

Is this problem BUS struct has method?? My program and i panic help me

 type BUS struct {
        Id       int64    `db:"Idx"`
        Created  int64
        Writer   string    `db:"Writer"`
        WriterId int64
        Title    string    `db:"Title"`
        Content  string    `db:"Content"`
        Want     int64
        status   int64
    }
func (b BUS) search(bf Board_find) []BUS {
    var arr []BUS
    query, query_map := bf.Prepare()
    _, err := dbmap.Select(&arr, query, query_map)
    if err != nil {
        log.Print(err)
    }
    return arr
}

func (b* BUS) write() {
    log.Print(reflect.TypeOf(b)) //just test code
    err := dbmap.Insert(b)
    check_err(err, "error in bus write")
}


func make_dbmap() *gorp.DbMap {
    db, err := sql.Open("mysql", "tester:tester@tcp(127.0.0.1:3306)/TEST")
    check_err(err, "db connection error")
    log.Println("db connection Ok")

    dialect := gorp.MySQLDialect{"InnoDB", "UTF8"}
    dbmap := &gorp.DbMap{Db: db, Dialect: dialect}

    AddTable(dbmap, USER_DB{}, "USER")
    table := AddTable(dbmap, BUS{}, "BUSBOARD")
    table.ColMap("Writer").SetMaxSize(10)
    table.ColMap("Title").SetMaxSize(25)
    table.ColMap("Content").SetMaxSize(50)
    log.Println("Add Table in gorp Ok")
    return dbmap
}

Answer 1

This error; reflect.Value.Interface: cannot return value obtained from unexported field or method is most likey due to status int64 being unexported (at least I see no other unexported fields that could cause it). The fix is as simple as upper casing Status.

In Go, fields on a struct with upper cased names are exported while those with lower case names are not. An unexported field is the nearest thing the language has to a 'private' field. In this case, gorp or whatever threw the error has reflected your type, found the status field and attempted to return it which is when you errored because the field is unexported.