golang 实现arrayColumn 将结构数组中结构内的某个字段作为map的key

func arrayColumn(array interface{},key string)(result map[string]interface{},err error){
	result = make(map[string]interface{})
	t := reflect.TypeOf(array)
	v := reflect.ValueOf(array)
	if t.Kind() != reflect.Slice {
		return nil, errors.New("array type not slice")
	}
	if v.Len() == 0{
		return nil, errors.New("array len is zero")
	}

	for i := 0; i < v.Len(); i++{
		indexv := v.Index(i)
		if indexv.Type().Kind() != reflect.Struct{
			return nil, errors.New("element type not struct")
		}
		mapKeyInterface := indexv.FieldByName(key)
		if mapKeyInterface.Kind() == reflect.Invalid {
			return nil,errors.New("key not exist")
		}
		mapKeyString, err := interfaceToString(mapKeyInterface.Interface())
		if err != nil{
			return nil, err
		}
		result[mapKeyString] = indexv.Interface()
	}
	return result,err
}

func interfaceToString(v interface{})(result string, err error){
	switch reflect.TypeOf(v).Kind(){
	case reflect.Int64,reflect.Int,reflect.Int8,reflect.Int16,reflect.Int32:
		result = fmt.Sprintf("%v",v)
	case reflect.Uint,reflect.Uint8,reflect.Uint16,reflect.Uint32,reflect.Uint64:
		result = fmt.Sprintf("%v",v)
	case reflect.String:
		result =  v.(string)
	default:
		err =  errors.New("can't transition to string")
	}
	return result,err
}