问题描述

我使用的是 dynamodb 对象持久性模型.

I was using dynamodb Object Persistence model.

DynamoDBTable("mydynamodbtablename")]
public class mytable
{
  ....
}

现在的问题是，如果我试图让表的名称在运行时动态更改(我通过配置文件获取表名)，我会收到错误

problem is now if I tried to make the name of the table to change dynamically in runtime (I get table names through config files), I get errors

var Table_Name = Config.GetTableName();
DynamoDBTable(Table_Name)]
public class mytable
{
  ....
}

错误:属性参数必须是属性参数类型xxx的常量表达式、typeof表达式或数组创建表达式

error: An attribute argument must be a constant expression, typeof expression or array creation expression of an attribute parameter type xxx

有没有办法(简单的方法)让我仍然可以使用 DDB 对象持久性模型并使表名动态化?

Is there a way (easy way) so that I can still use DDB Object Persistence Model and make tables name dynamic?

更新:

好像我没有说清楚ddb持久化模型.这是官方文档http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/CRUDHighLevelExample1.html

It seems that I didn't mentioned ddb persistence model clearly. Here is the official document http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/CRUDHighLevelExample1.html

这是一个例子，说明我们在实际实践中如何使用对象持久性模型

and here is an example of how in real practice do we use object persistence model

var records = await context.LoadAsync<mytable>(somekey);
foreach(var item in records)
{
   ....
}

推荐答案

使用接受 DynamoDBOperationConfig 的 LoadAsync 方法的重载:

Use the overload of the LoadAsync<T> method that accepts a DynamoDBOperationConfig:

var config = new DynamoDBOperationConfig 
{ 
    OverrideTableName = "MyTableName"
};
var records = await context.LoadAsync<mytable>(somekey, config);
foreach(var item in records)
{
   ....
}

这篇关于如何使用对象持久性模型在 C# 中动态更改 dynamodb 表名的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持编程学习网！