[InvalidOperationException: 超时时间已到。超时时间已到，但是尚未从池中获取连接。出现这种情况可能是因为所有池连接均在使用，并且达到了最大池大小。]
   System.Data.ProviderBase.DbConnectionFactory.GetConnection(DbConnection owningConnection) +1282933
   System.Data.ProviderBase.DbConnectionClosed.OpenConnection(DbConnection outerConnection, DbConnectionFactory connectionFactory) +105
   System.Data.SqlClient.SqlConnection.Open() +111
   SYEXAM.SQLServerDAL.SQLHelper.ExecuteReader(String query, SqlParameter[] parameters) in E:\C＃程序\SYEXAM\SYEXAM.SQLServerDAL\SQLHelper.cs:229
   SYEXAM.SQLServerDAL.NewDAL.GetNewByID(String _ID) in E:\C＃程序\SYEXAM\SYEXAM.SQLServerDAL\NewDAL.cs:26
   SYEXAM.BLL.NewBLL.GetNewByID(String _ID) in E:\C＃程序\SYEXAM\SYEXAM.BLL\New\NewBLL.cs:23
   SYEXAM.Webs.InnerXml.Page_Load(Object sender, EventArgs e) +125
   System.Web.Util.CalliHelper.EventArgFunctionCaller(IntPtr fp, Object o, Object t, EventArgs e) +15
   System.Web.Util.CalliEventHandlerDelegateProxy.Callback(Object sender, EventArgs e) +33
   System.EventHandler.Invoke(Object sender, EventArgs e) +0
   System.Web.UI.Control.OnLoad(EventArgs e) +99
   System.Web.UI.Control.LoadRecursive() +47
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +1436