golang 无法为结构分配接口 {}

Question

专家您好，我正在使用此库将 K/V 存储在缓存中"github.com/bluele/gcache"我存储的值就是这个数据结构type LatestBlockhashCacheResult struct {    Blockhash            string `json:"blockhash"`    LastValidBlockHeight uint64 `json:"lastValidBlockHeight"` // Slot.    CommitmentType  string `json:"commitmentType"`}lbhr := LatestBlockhashCacheResult{            Blockhash:            lbh.Value.Blockhash.String(),            LastValidBlockHeight: lbh.Value.LastValidBlockHeight,            CommitmentType:       string(commitmentType),        }        gc.SetWithExpire(lbh.Value.LastValidBlockHeight, lbhr, time.Hour*10)我对检索缓存没有问题，但无法对其进行类型转换c, _ := gc.Get(rf.LastValidBlockHeight)    fmt.Printf("%T\n", c)所以当我尝试这个var c = LatestBlockhashCacheResult{}    c, _ = gc.Get(rf.LastValidBlockHeight)这引发了我的错误 cannot assign interface {} to c (type LatestBlockhashCacheResult) in multiple assignment: need type assertion

Answer 1

您正在尝试分配interface{}给类型化变量。为此，您需要首先尝试将interface{}值转换为特定类型

val, err := gc.Get(rf.LastValidBlockHeight)

if err != nil {

  // handle 

}

c, ok := val.(LatestBlockhashCacheResult)

if !ok {

   // val has different type than LatestBlockhashCacheResult

}

参考：https:

//go.dev/tour/methods/15

https://go.dev/tour/methods/16