我开发的应用程序每周完全崩溃大约2次。当它崩溃时，它将取消整个应用程序，直到应用程序池被回收。我无法在开发环境中重现错误。
下面我粘贴了导致崩溃的代码和来自应用程序事件查看器的错误消息。 崩溃应用程序的行以~~~~ 开头。该消息指出我有一个打开的DataReader，但我检查了我的代码，并且我总是关闭我的数据读取器和连接。
我不知道应该采取什么步骤来解决这个问题。任何帮助将不胜感激。谢谢！
public bool open() {
//-- check if connection is closed
if (this.dbconn.State == System.Data.ConnectionState.Closed) {
try {
this.dbconn.Open();
}
catch (Exception ex) {
this.errorCode = (int)DatabaseErrorType.DBOpenFailed;
this.errorMessage = System.Web.HttpUtility.HtmlEncode(ex.Message);
throw ex;
}
}
return true;
}
/// <summary> closes connection object</summary>
public bool close() {
if (!(this.dbconn == null)) {
if (!(this.dbconn.State == System.Data.ConnectionState.Closed)) {
try {
this.dbconn.Close();
}
catch (Exception ex) {
this.errorCode = (int)DatabaseErrorType.DBCloseFailed;
this.errorMessage = System.Web.HttpUtility.HtmlEncode(ex.Message);
return false;
}
}
}
return true;
}
// GET MULTI Accounts
public List<DTO.DTOAccount> GetAccounts(DTO.DTOAccount objAcc) {
//-- reset error variables
resetError();
// make sure the connection is open
if (this.open()) {
SqlDataReader sqlReader = null;
try {
SqlCommand sqlProcedure = new SqlCommand("[dbo].[sp_Select_ONECARD_ACCOUNTS]", this.dbconn);
sqlProcedure.CommandType = System.Data.CommandType.StoredProcedure;
sqlProcedure.Parameters.Add(new SqlParameter("@ACCOUNT" , objAcc.AccountId));
sqlProcedure.Parameters.Add(new SqlParameter("@UDEF_4" , objAcc.UDEF_4));
~~~~sqlReader = sqlProcedure.ExecuteReader();
List<DTO.DTOAccount> Accounts = new List<DTO.DTOAccount>();
// iterate through all values returned
while (sqlReader.Read()) {
DTO.DTOAccount tmpAccount = new ca.eyecode.onecard.DTO.DTOAccount();
tmpAccount.AccountId = (String)sqlReader["ACCOUNT"];
tmpAccount.Category = (String)sqlReader["CATEGORY"];
tmpAccount.Groups = (String)sqlReader["GROUPS"];
tmpAccount.Suffix = (String)sqlReader["SUFFIX"];
tmpAccount.UDEF_1 = ((String)sqlReader["UDEF_1"]).Trim();
tmpAccount.UDEF_4 = ((String)sqlReader["UDEF_4"]).Trim();
tmpAccount.FirstName = ((String)sqlReader["FNAME"]).Trim();
tmpAccount.LastName = ((String)sqlReader["LNAME"]).Trim();
tmpAccount.Picture = (sqlReader["PICTURE"] == DBNull.Value ? String.Empty : (String)sqlReader["PICTURE"]).Trim();
// add account items
tmpAccount.AccountItems.Add (new DTO.DTOAccountItem() { Account= AccountType.ONEcardCash, Balance= Convert.ToDouble((Decimal)sqlReader["BALANCE_1"])});
tmpAccount.AccountItems.Add (new DTO.DTOAccountItem() { Account= AccountType.Department, Balance= Convert.ToDouble((Decimal)sqlReader["BALANCE_2"])});
tmpAccount.AccountItems.Add (new DTO.DTOAccountItem() { Account= AccountType.BookStore, Balance= Convert.ToDouble((Decimal)sqlReader["BALANCE_3"])});
tmpAccount.AccountItems.Add (new DTO.DTOAccountItem() { Account= AccountType.TechBalance, Balance= Convert.ToDouble((Decimal)sqlReader["BALANCE_4"])});
tmpAccount.AccountItems.Add (new DTO.DTOAccountItem() { Account= AccountType.Bonus1, Balance= Convert.ToDouble((Decimal)sqlReader["BALANCE_5"])});
tmpAccount.AccountItems.Add (new DTO.DTOAccountItem() { Account= AccountType.MealPlanExtra, Balance= Convert.ToDouble((Decimal)sqlReader["BALANCE_6"])});
tmpAccount.AccountItems.Add (new DTO.DTOAccountItem() { Account= AccountType.MealPlanDollars, Balance= Convert.ToDouble((Decimal)sqlReader["BALANCE_7"])});
tmpAccount.AccountItems.Add (new DTO.DTOAccountItem() { Account= AccountType.AramarkCredit, Balance= Convert.ToDouble((Decimal)sqlReader["BALANCE_8"])});
tmpAccount.AccountItems.Add (new DTO.DTOAccountItem() { Account= AccountType.AramarkEmployees, Balance= Convert.ToDouble((Decimal)sqlReader["BALANCE_9"])});
// Combine Totals to One Meal PLAN
tmpAccount.AccountItems[5].Balance += tmpAccount.AccountItems[6].Balance;
tmpAccount.AccountItems[5].Balance += tmpAccount.AccountItems[8].Balance;
tmpAccount.AccountItems[6].Balance = 0;
tmpAccount.AccountItems[8].Balance = 0;
Accounts.Add(tmpAccount);
}
return Accounts;
}
finally {
try {
if (sqlReader != null) {
sqlReader.Close();
}
}
catch {}
this.close();
}
}
return null;
}
ERROR
Event code: 3005
Event message: An unhandled exception has occurred.
Event time: 4/19/2012 11:30:39 AM
Event time (UTC): 4/19/2012 5:30:39 PM
Event ID: 7715c17b872240829c3dfb562268998e
Event sequence: 1253
Event occurrence: 1
Event detail code: 0
Application information:
Application domain: /LM/W3SVC/997719702/Root-1-129793277036652335
Trust level: Full
Application Virtual Path: /
Application Path:
Machine name:
Process information:
Process ID: 820
Process name: w3wp.exe
Account name:
Exception information:
Exception type: InvalidOperationException
Exception message: There is already an open DataReader associated with this Command which must be closed first.
at System.Data.SqlClient.SqlInternalConnectionTds.ValidateConnectionForExecute(SqlCommand command)
at System.Data.SqlClient.SqlCommand.ValidateCommand(String method, Boolean async)
at System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method, DbAsyncResult result)
at System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method)
at System.Data.SqlClient.SqlCommand.ExecuteReader(CommandBehavior behavior, String method)
at System.Data.SqlClient.SqlCommand.ExecuteReader()
at ca.eyecode.onecard.DAO.DAOAccount.GetAccounts(DTOAccount objAcc) in C:\inetpub\wwwroot\ONEcard\OneAccount\OneAccount\Models\ca.eyecode\onecard\DAO\DAOAccount.cs:line 47
at ca.eyecode.onecard.BL.BLAccount.AccountsGet(DTOAccount objAcc) in C:\inetpub\wwwroot\ONEcard\OneAccount\OneAccount\Models\ca.eyecode\onecard\BL\BLAccount.cs:line 228
at ca.eyecode.onecard.BL.BLAccount.AccountLogin(String CCID, String Password) in C:\inetpub\wwwroot\ONEcard\OneAccount\OneAccount\Models\ca.eyecode\onecard\BL\BLAccount.cs:line 171
at ca.eyecode.onecard.BL.BLFacade.AccountLogin(String CCID, String Password) in C:\inetpub\wwwroot\ONEcard\OneAccount\OneAccount\Models\ca.eyecode\onecard\BL\BLFacade.cs:line 36
at ca.eyecode.onecard.Controllers.HomeController.Index(String inpCCID, String inpPASS) in C:\inetpub\wwwroot\ONEcard\OneAccount\OneAccount\Controllers\HomeController.cs:line 77
at lambda_method(Closure , ControllerBase , Object[] )
at System.Web.Mvc.ReflectedActionDescriptor.Execute(ControllerContext controllerContext, IDictionary`2 parameters)
at System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary`2 parameters)
at System.Web.Mvc.ControllerActionInvoker.<>c__DisplayClassd.<InvokeActionMethodWithFilters>b__a()
at System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodFilter(IActionFilter filter, ActionExecutingContext preContext, Func`1 continuation)
at System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodFilter(IActionFilter filter, ActionExecutingContext preContext, Func`1 continuation)
at System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodWithFilters(ControllerContext controllerContext, IList`1 filters, ActionDescriptor actionDescriptor, IDictionary`2 parameters)
at System.Web.Mvc.ControllerActionInvoker.InvokeAction(ControllerContext controllerContext, String actionName)
at System.Web.Mvc.Controller.ExecuteCore()
at System.Web.Mvc.MvcHandler.<>c__DisplayClass8.<BeginProcessRequest>b__4()
at System.Web.Mvc.Async.AsyncResultWrapper.<>c__DisplayClass1.<MakeVoidDelegate>b__0()
at System.Web.HttpApplication.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute()
at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)
Request information:
Request URL:
Request path: /
User host address:
User:
Is authenticated: False
Authentication Type:
Thread account name:
Thread information:
Thread ID: 9
Thread account name:
Is impersonating: False
Stack trace: at System.Data.SqlClient.SqlInternalConnectionTds.ValidateConnectionForExecute(SqlCommand command)
at System.Data.SqlClient.SqlCommand.ValidateCommand(String method, Boolean async)
at System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method, DbAsyncResult result)
at System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method)
at System.Data.SqlClient.SqlCommand.ExecuteReader(CommandBehavior behavior, String method)
at System.Data.SqlClient.SqlCommand.ExecuteReader()
at ca.eyecode.onecard.DAO.DAOAccount.GetAccounts(DTOAccount objAcc) in C:\inetpub\wwwroot\ONEcard\OneAccount\OneAccount\Models\ca.eyecode\onecard\DAO\DAOAccount.cs:line 47
at ca.eyecode.onecard.BL.BLAccount.AccountsGet(DTOAccount objAcc) in C:\inetpub\wwwroot\ONEcard\OneAccount\OneAccount\Models\ca.eyecode\onecard\BL\BLAccount.cs:line 228
at ca.eyecode.onecard.BL.BLAccount.AccountLogin(String CCID, String Password) in C:\inetpub\wwwroot\ONEcard\OneAccount\OneAccount\Models\ca.eyecode\onecard\BL\BLAccount.cs:line 171
at ca.eyecode.onecard.BL.BLFacade.AccountLogin(String CCID, String Password) in C:\inetpub\wwwroot\ONEcard\OneAccount\OneAccount\Models\ca.eyecode\onecard\BL\BLFacade.cs:line 36
at ca.eyecode.onecard.Controllers.HomeController.Index(String inpCCID, String inpPASS) in C:\inetpub\wwwroot\ONEcard\OneAccount\OneAccount\Controllers\HomeController.cs:line 77
at lambda_method(Closure , ControllerBase , Object[] )
at System.Web.Mvc.ReflectedActionDescriptor.Execute(ControllerContext controllerContext, IDictionary`2 parameters)
at System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary`2 parameters)
at System.Web.Mvc.ControllerActionInvoker.<>c__DisplayClassd.<InvokeActionMethodWithFilters>b__a()
at System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodFilter(IActionFilter filter, ActionExecutingContext preContext, Func`1 continuation)
at System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodFilter(IActionFilter filter, ActionExecutingContext preContext, Func`1 continuation)
at System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodWithFilters(ControllerContext controllerContext, IList`1 filters, ActionDescriptor actionDescriptor, IDictionary`2 parameters)
at System.Web.Mvc.ControllerActionInvoker.InvokeAction(ControllerContext controllerContext, String actionName)
at System.Web.Mvc.Controller.ExecuteCore()
at System.Web.Mvc.MvcHandler.<>c__DisplayClass8.<BeginProcessRequest>b__4()
at System.Web.Mvc.Async.AsyncResultWrapper.<>c__DisplayClass1.<MakeVoidDelegate>b__0()
at System.Web.HttpApplication.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute()
at System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously)
答案 0 :(得分：1)
可以肯定的是，您可以开始在using周围使用SqlDataReader声明。对其他元素也这样做。这样你确定他们总是被处理和关闭。
接下来，请确保不嵌套SqlDataReaders。尽快关闭它们，并按顺序进行数据访问。这应该可以解决问题。
答案 1 :(得分：1)
问题是我在代码中尝试了finally块。在处理的异常中，保证运行关联的finally块。但是，如果未处理异常，则finally块的执行取决于如何触发异常展开操作。反过来，这取决于您的计算机的设置方式。
确保每次都不能省略catch块时执行finally块。 http://msdn.microsoft.com/en-us/library/zwc8s4fz(v=vs.100).aspx
答案 2 :(得分：0)
除非你真的需要其他地方的连接对象，否则我会将方法重构为：
public List<DTO.DTOAccount> GetAccounts(DTO.DTOAccount objAcc)
{
//-- reset error variables
resetError();
List<DTO.DTOAccount> Accounts = new List<DTO.DTOAccount>();
try
{
using (SqlConnection dbconn = new SqlConnection("your-connection-string"))
{
using (SqlCommand sqlProcedure = new SqlCommand("[dbo].[sp_Select_ONECARD_ACCOUNTS]", dbconn))
{
sqlProcedure.CommandType = System.Data.CommandType.StoredProcedure;
sqlProcedure.Parameters.Add(new SqlParameter("@ACCOUNT", objAcc.AccountId));
sqlProcedure.Parameters.Add(new SqlParameter("@UDEF_4", objAcc.UDEF_4));
dbconn.Open();
using (SqlDataReader sqlReader = sqlProcedure.ExecuteReader())
{
while (sqlReader.Read())
{
DTO.DTOAccount tmpAccount = new ca.eyecode.onecard.DTO.DTOAccount();
tmpAccount.AccountId = (String)sqlReader["ACCOUNT"];
tmpAccount.Category = (String)sqlReader["CATEGORY"];
tmpAccount.Groups = (String)sqlReader["GROUPS"];
tmpAccount.Suffix = (String)sqlReader["SUFFIX"];
tmpAccount.UDEF_1 = ((String)sqlReader["UDEF_1"]).Trim();
tmpAccount.UDEF_4 = ((String)sqlReader["UDEF_4"]).Trim();
tmpAccount.FirstName = ((String)sqlReader["FNAME"]).Trim();
tmpAccount.LastName = ((String)sqlReader["LNAME"]).Trim();
tmpAccount.Picture = (sqlReader["PICTURE"] == DBNull.Value ? String.Empty : (String)sqlReader["PICTURE"]).Trim();
// add account items
tmpAccount.AccountItems.Add(new DTO.DTOAccountItem() { Account = AccountType.ONEcardCash, Balance = Convert.ToDouble((Decimal)sqlReader["BALANCE_1"]) });
tmpAccount.AccountItems.Add(new DTO.DTOAccountItem() { Account = AccountType.Department, Balance = Convert.ToDouble((Decimal)sqlReader["BALANCE_2"]) });
tmpAccount.AccountItems.Add(new DTO.DTOAccountItem() { Account = AccountType.BookStore, Balance = Convert.ToDouble((Decimal)sqlReader["BALANCE_3"]) });
tmpAccount.AccountItems.Add(new DTO.DTOAccountItem() { Account = AccountType.TechBalance, Balance = Convert.ToDouble((Decimal)sqlReader["BALANCE_4"]) });
tmpAccount.AccountItems.Add(new DTO.DTOAccountItem() { Account = AccountType.Bonus1, Balance = Convert.ToDouble((Decimal)sqlReader["BALANCE_5"]) });
tmpAccount.AccountItems.Add(new DTO.DTOAccountItem() { Account = AccountType.MealPlanExtra, Balance = Convert.ToDouble((Decimal)sqlReader["BALANCE_6"]) });
tmpAccount.AccountItems.Add(new DTO.DTOAccountItem() { Account = AccountType.MealPlanDollars, Balance = Convert.ToDouble((Decimal)sqlReader["BALANCE_7"]) });
tmpAccount.AccountItems.Add(new DTO.DTOAccountItem() { Account = AccountType.AramarkCredit, Balance = Convert.ToDouble((Decimal)sqlReader["BALANCE_8"]) });
tmpAccount.AccountItems.Add(new DTO.DTOAccountItem() { Account = AccountType.AramarkEmployees, Balance = Convert.ToDouble((Decimal)sqlReader["BALANCE_9"]) });
// Combine Totals to One Meal PLAN
tmpAccount.AccountItems[5].Balance += tmpAccount.AccountItems[6].Balance;
tmpAccount.AccountItems[5].Balance += tmpAccount.AccountItems[8].Balance;
tmpAccount.AccountItems[6].Balance = 0;
tmpAccount.AccountItems[8].Balance = 0;
Accounts.Add(tmpAccount);
}
}
}
}
}
catch
{
// do some error handling.
}
return Accounts;
}