asp.net-mvc - 临时数据持久化

Question

我最近一直在使用 TempData 并面临一个令人困惑的情况:

假设TempData是在以下Action中创建的:

public ActionResult MyAction1()
{
  //...
  myTempData = TempData["myTempData"];
  //..
}

预计将在以下操作中使用:

public ActionResult MyAction2()
{
  //...
  TempData["myTempData"] = myTempData;
  //..
}

据我所知，如果我在下一个请求中调用 MyAction2，TempData 值将被删除。但是，如果我在下一个请求时调用其他操作，而不是 MyAction2，TempData 是否会被删除？如果是的话，有什么技巧可以确保它存在直到 session 结束吗？

谢谢大家。

Answer 1

在这里，您可以为下一个请求保留并查看临时数据:

如果您不读取临时数据，那么它将可用于下一个后续请求

So let’s discuss these four conditions in more detail

“Tempdata helps to preserve values for a single request”.

The other half-truth which developers do not know is or I will say which confuses developer is:

“TempData CAN ALSO preserve values for the next request depending on 4 conditions”..

1. Not Read
2. Normal Read
3. Read and Keep
4. Peek and Read

Condition 1 (Not read): If you set a “TempData” inside your action and if you do not read it in your view, then “TempData” will be persisted for the next request.

Condition 2 (Normal Read): If you read the “TempData” normally like the below code, it will not persist for the next request.

   stringstr = TempData["MyData"];

Even if you are displaying, it’s a normal read like the code below:

   @TempData["MyData"];

Condition 3 (Read and Keep): If you read the “TempData” and call the “Keep” method, it will be persisted.

   @TempData["MyData"];
   TempData.Keep("MyData");

Condition 4 ( Peek and Read): If you read “TempData” by using the “Peek” method, it will persist for the next request.

   stringstr = TempData.Peek("Td").ToString();