// 范围扫描
func (d *DB) Enumerate(iter *gorocksdb.Iterator, min, max []byte, direction IterDirection, fn func(i int, key, value []byte, quit *bool)) {
found := false
if direction == IterBackward {
if len(max) == 0 {
iter.SeekToLast()
} else {
iter.Seek(max)
}
} else {
if len(min) == 0 {
iter.SeekToFirst()
} else {
iter.Seek(min)
}
}
found = iter.Valid()
if !found {
return
}
i := -1
// 范围判断
if found && between(iter.Key().Data(), min, max) {
i++
quit := false
fn(i, iter.Key().Data(), iter.Value().Data(), &quit)
if quit {
return
}
}
for {
found = false
if direction == IterBackward {
iter.Prev()
} else {
iter.Next()
}
found = iter.Valid()
if found && between(iter.Key().Data(), min, max) {
i++
quit := false
fn(i, iter.Key().Data(), iter.Value().Data(), &quit)
if quit {
return
}
} else {
break
}
}
return
}
