如何从（Yesod/Haskell项目）的会话中获取用户ID

伙计们，我有一个小程序，我需要从会话中提取用户的ID

我不能把它放在Text/Int中，因为它说会话带有一个键（我想是Sql键），我如何将它转换为Int以用于我的项目中的其他方法

我试图从会话中恢复ID

getInicioR :: Handler Html
getInicioR = do
        uid <- lookupSession "_ID"
        user <- runDB $ get404 uid 

---

使用

keyToValues

获取值列表

例如，如果您知道该键是一个文本值，那么您的列表将由一个

PersistText

值组成，您可以这样操作：

do uid <- lookupSession "_ID"
   let pvals = keyToValues uid
       [ PersistText txt ] = pvals
   liftIO $ print pvals            -- to see what pvals is
   -- now txt is a Text value
   ...

douid
keyToValues :: Key record -> [PersistValue]

do uid <- lookupSession "_ID"
   let pvals = keyToValues uid
       [ PersistText txt ] = pvals
   liftIO $ print pvals            -- to see what pvals is
   -- now txt is a Text value
   ...