How to extract data from an Excel file with C# / FileHelpers ExcelNPOIStorage

I am trying to extract data from an Excel sheet with Filehelpers ExcelNPOIStorage. Therefore I created a class :

public static class UalExcelReader
    {
        public static UalShipmentRecord[] ReadInput(String pathToFile)
        {
            var provider = new ExcelNPOIStorage(typeof (UalShipmentRecord))
            {
                StartRow = 2,
                StartColumn = 1,
                FileName = pathToFile
            };
            var res = (UalShipmentRecord[]) provider.ExtractRecords();
            return res;
        }
    }

and of course the model class:

[DelimitedRecord("|")]
public class UalShipmentRecord
{
    public string contentofcol1;
    public string contentofcol2;
    ...

}

But I am getting an IndexOutOfRangeException calling ExtractRecords():

System.IndexOutOfRangeException was unhandled
  HResult=-2146233080
  Message=Index was outside the bounds of the array.
  Source=FileHelpers
  StackTrace:
       at FileHelpers.RecordOperations.ValuesToRecord(Object[] values)
       at FileHelpers.DataLink.DataStorage.ValuesToRecord(Object[] values)
       at FileHelpers.ExcelNPOIStorage.ExcelNPOIStorage.ExtractRecords()
       at Test.Controller.UalExcelReader.ReadInput(String pathToFile) in c:\TEMP\test\Test\Test\Test\Controller\UalExcelReader.cs:line 17
       at Test.App.OnStartup(StartupEventArgs eventArgs) in c:\TEMP\test\Test\Test\Test\App.xaml.cs:line 23
       at System.Windows.Application.<.ctor>b__1(Object unused)
       at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
       at MS.Internal.Threading.ExceptionFilterHelper.TryCatchWhen(Object source, Delegate method, Object args, Int32 numArgs, Delegate catchHandler)
       at System.Windows.Threading.DispatcherOperation.InvokeImpl()
       at System.Windows.Threading.DispatcherOperation.InvokeInSecurityContext(Object state)
       at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
       at System.Windows.Threading.DispatcherOperation.Invoke()
       at System.Windows.Threading.Dispatcher.ProcessQueue()
       at System.Windows.Threading.Dispatcher.WndProcHook(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
       at MS.Win32.HwndWrapper.WndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
       at MS.Win32.HwndSubclass.DispatcherCallbackOperation(Object o)
       at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
       at MS.Internal.Threading.ExceptionFilterHelper.TryCatchWhen(Object source, Delegate method, Object args, Int32 numArgs, Delegate catchHandler)
       at System.Windows.Threading.Dispatcher.LegacyInvokeImpl(DispatcherPriority priority, TimeSpan timeout, Delegate method, Object args, Int32 numArgs)
       at MS.Win32.HwndSubclass.SubclassWndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam)
       at MS.Win32.UnsafeNativeMethods.DispatchMessage(MSG& msg)
       at System.Windows.Threading.Dispatcher.PushFrameImpl(DispatcherFrame frame)
       at System.Windows.Threading.Dispatcher.PushFrame(DispatcherFrame frame)
       at System.Windows.Threading.Dispatcher.Run()
       at System.Windows.Application.RunDispatcher(Object ignore)
       at System.Windows.Application.RunInternal(Window window)
       at System.Windows.Application.Run(Window window)
       at System.Windows.Application.Run()
       at Test.App.Main() in c:\TEMP\test\Test\Test\Test\obj\Debug\App.g.cs:line 0
       at System.AppDomain._nExecuteAssembly(RuntimeAssembly 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.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
       at System.Threading.ThreadHelper.ThreadStart()
  InnerException:

Am I using it correctly? Is there an example that I could look at?

Answer：

  private void OpenWorkbook(string filename)
    {
        FileInfo info = new FileInfo(filename);
        if (info.Exists == false)
            throw new FileNotFoundException(string.Concat("Excel File '", filename, "' not found."), filename);

        using (FileStream file = new FileStream(filename, FileMode.Open, FileAccess.Read)) {
            var extension = Path.GetExtension(filename);
            if (extension.ToLowerInvariant() == ".xlsx" || extension.ToLowerInvariant() == ".xlsm")
            {
                mWorkbook = new XSSFWorkbook(file);
            }
            else
                mWorkbook = new HSSFWorkbook(file);
            // Next line fix
            Line 101 - mWorkbook.MissingCellPolicy = MissingCellPolicy.CREATE_NULL_AS_BLANK;
            // Previous line fix  
            if (String.IsNullOrEmpty(SheetName))
                mSheet = mWorkbook.GetSheetAt(mWorkbook.ActiveSheetIndex);  
            else {
                try {
                    mSheet = mWorkbook.GetSheet(SheetName);
                    if (mSheet == null) {
                        throw new ExcelBadUsageException(string.Concat("The sheet '",
                            SheetName,
                            "' was not found in the workbook."));
                    }

                    var sheetIndex = mWorkbook.GetSheetIndex(mSheet);
                    mWorkbook.SetActiveSheet(sheetIndex);
                }
                catch {
                    throw new ExcelBadUsageException(string.Concat("The sheet '",
                        SheetName,
                        "' was not found in the workbook."));
                }
            }
        }
    }

Answer：

Tags: c#c#, excel, file