How to catch all exceptions in c# using try and catch?

Solution 1:

Both approaches will catch all exceptions. There is no significant difference between your two code examples except that the first will generate a compiler warning because ex is declared but not used.

But note that some exceptions are special and will be rethrown automatically.

ThreadAbortException is a special exception that can be caught, but it will automatically be raised again at the end of the catch block.

http://msdn.microsoft.com/en-us/library/system.threading.threadabortexception.aspx

As mentioned in the comments, it is usually a very bad idea to catch and ignore all exceptions. Usually you want to do one of the following instead:

• Catch and ignore a specific exception that you know is not fatal.

  catch (SomeSpecificException)
  {
      // Ignore this exception.
  }
  

• Catch and log all exceptions.

  catch (Exception e)
  {
      // Something unexpected went wrong.
      Log(e);
      // Maybe it is also necessary to terminate / restart the application.
  }
  

• Catch all exceptions, do some cleanup, then rethrow the exception.

  catch
  {
      SomeCleanUp();
      throw;
  }
  

Note that in the last case the exception is rethrown using throw; and not throw ex;.

Solution 2:

Note that besides all other comments there is a small difference, which should be mentioned here for completeness!

With the empty catch clause you can catch non-CLSCompliant Exceptions when the assembly is marked with "RuntimeCompatibility(WrapNonExceptionThrows = false)" (which is true by default since CLR2). [1][2][3]

[1] http://msdn.microsoft.com/en-us/library/bb264489.aspx

[2] https://web.archive.org/web/20140816175210/http://blogs.msdn.com/b/pedram/archive/2007/01/07/non-cls-exceptions.aspx

[3] Will CLR handle both CLS-compliant and non-CLS compliant exceptions?

Solution 3:

I catch all the exceptions and store it in database, so errors can be corrected easily - the page, place, date etc stored

try
{     
   Cart = DB.BuyOnlineCartMasters.Where(c => c.CmpyID == LoginID && c.Active == true).FirstOrDefault();
}
catch (Exception e)
{
    ErrorReport.StoreError("CartMinifiedPartial-Company", e);  
    -- storing the error for reference
}

Storing

public static void StoreError(string ErrorPage, Exception e)
    {
        try
        {
            eDurar.Models.db_edurarEntities1 DB = new Models.db_edurarEntities1();
            eDurar.Models.ErrorTable Err = new eDurar.Models.ErrorTable();
            Err.ErrorPage = ErrorPage;
            if (e.Message != null)
            {
                Err.ErrorDetails = e.Message;
            }
            if (e.InnerException != null)
            {
                Err.InnerException = e.InnerException.Message.ToString();
            }

            Err.Date = TimeZoneInfo.ConvertTimeFromUtc(DateTime.UtcNow, TimeZoneInfo.FindSystemTimeZoneById("India Standard Time"));
            DB.ErrorTables.AddObject(Err);
            DB.SaveChanges();
}

Solution 4:

    static void Main(string[] args)
    {
        AppDomain.CurrentDomain.UnhandledException += CurrentDomain_UnhandledException;
    }

    static void CurrentDomain_UnhandledException(object sender, UnhandledExceptionEventArgs e)
    {
        throw new NotImplementedException();
    }