我试图从数据库中提取一些二进制数据并将其写入PDF文件。 大多数情况下，这都进行得很顺利，但是偶尔会出现一个数据行导致特定的错误-
超时已过期。 在操作完成之前超时时间已过或服务器未响应。
请记住，这仅发生在少数几行上，而且永远不是随机的。 相同的行始终引发异常。 我不太确定为什么会引发异常，但是我可以跳过引起问题的行并继续进行。 然而，我的问题是当我捕获异常然后尝试继续到下一行时，我遇到了另一个异常-
无效操作异常-尝试在读取器关闭时调用Read方法。
这是否意味着读取器遇到异常后会自动关闭？ 如何在没有任何问题的情况下继续进行下一行？
while (sdrReader.Read()) // Second exception happens here
{
try
{
byte[] byteData = new Byte[(sdrReader.GetBytes(0, 0, null, 0, int.MaxValue))]; // first exception happens here
sdrReader.GetBytes(0, 0, byteData, 0, byteData.Length);
string strOutputFileName = sdrReader.GetInt32(1).ToString() + ".pdf";
msMemoryStreams = new MemoryStream();
msMemoryStreams.Write(byteData, 0, byteData.Length);
byte[] byteArray = msMemoryStreams.ToArray();
msMemoryStreams.Flush();
msMemoryStreams.Close();
writeByteArrayToFile(byteData, txtFilesPath.Text + "\\" + strOutputFileName);
}
catch (Exception e)
{
Logger.Write("Document failed to convert: " + e.Message);
}
}
如您所请求的那样，以下是堆栈跟踪：
at System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection)
at System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj)
at System.Data.SqlClient.TdsParserStateObject.ReadSniError(TdsParserStateObject stateObj, UInt32 error)
at System.Data.SqlClient.TdsParserStateObject.ReadSni(DbAsyncResult asyncResult, TdsParserStateObject stateObj)
at System.Data.SqlClient.TdsParserStateObject.ReadNetworkPacket()
at System.Data.SqlClient.TdsParserStateObject.ReadBuffer()
at System.Data.SqlClient.TdsParserStateObject.ReadByteArray(Byte[] buff, Int32 offset, Int32 len)
at System.Data.SqlClient.TdsParser.ReadSqlValue(SqlBuffer value, SqlMetaDataPriv md, Int32 length, TdsParserStateObject stateObj)
at System.Data.SqlClient.SqlDataReader.ReadColumnData()
at System.Data.SqlClient.SqlDataReader.ReadColumn(Int32 i, Boolean setTimeout)
at System.Data.SqlClient.SqlDataReader.GetSqlBinary(Int32 i)
at System.Data.SqlClient.SqlDataReader.GetBytesInternal(Int32 i, Int64 dataIndex, Byte[] buffer, Int32 bufferIndex, Int32 length)
at System.Data.SqlClient.SqlDataReader.GetBytes(Int32 i, Int64 dataIndex, Byte[] buffer, Int32 bufferIndex, Int32 length)
at Pdf2Rtf.Form1.Read() in F:\Code\Pdf2Rtf\Pdf2Rtf\Pdf2Rtf\Form1.cs:line 77
at Pdf2Rtf.Form1.btnRead_Click(Object sender, EventArgs e) in F:\Code\Pdf2Rtf\Pdf2Rtf\Pdf2Rtf\Form1.cs:line 24
at System.Windows.Forms.Control.OnClick(EventArgs e)
at System.Windows.Forms.Button.OnClick(EventArgs e)
at System.Windows.Forms.Button.OnMouseUp(MouseEventArgs mevent)
at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)
at System.Windows.Forms.Control.WndProc(Message& m)
at System.Windows.Forms.ButtonBase.WndProc(Message& m)
at System.Windows.Forms.Button.WndProc(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
at System.Windows.Forms.UnsafeNativeMethods.DispatchMessageW(MSG& msg)
at System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(Int32 dwComponentID, Int32 reason, Int32 pvLoopData)
at System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(Int32 reason, ApplicationContext context)
at System.Windows.Forms.Application.ThreadContext.RunMessageLoop(Int32 reason, ApplicationContext context)
at System.Windows.Forms.Application.Run(Form mainForm)
at Pdf2Rtf.Program.Main() in F:\Code\Pdf2Rtf\Pdf2Rtf\Pdf2Rtf\Program.cs:line 18
at System.AppDomain._nExecuteAssembly(Assembly assembly, String[] args)
at System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
at System.Threading.ThreadHelper.ThreadStart()