Learn how to use exception filtering technique introduced in C# 6.0.
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Code Samples
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namespace ExceptionFilters { class Program { static int Main(string[] args) { #region Old way of filtering exceptions int recoveryMode; try { DoOperation(null); //DoOperation(1,2,3,4); } catch (ArgumentOutOfRangeException ae) { LogException(ae); if (CanRecover(ae)) { Recover(ae); } else if (CanRecover(ae, out recoveryMode)) { Recover(ae, recoveryMode); } else if (ae.Message.Contains("warning")) { Recover(ae); } else { throw; } } catch (Exception e) { LogException(e); if (CanRecover(e)) { Recover(e); } else if (CanRecover(e, out recoveryMode)) { Recover(e, recoveryMode); } else if (e.Message.Contains("warning")) { Recover(e); } else { throw; } } #endregion Old way of filtering exceptions #region Exception Filters //return 0; try { DoOperation(null); //DoOperation(1,2,3,4); } catch (Exception e) when (LogException(e)) { //This block is intentianally left empty, just an exception is logged //in an exception filter } catch (Exception e) when (CanRecover(e)) { Recover(e); } catch (Exception e) when (CanRecover(e, out recoveryMode)) { Recover(e, recoveryMode); } catch( Exception e) when (e.Message.Contains("warning")) { Recover(e); } catch(ArgumentNullException ane) { //Handle argument null exception } #endregion Exception Filters return 0; //Success } #region Helper Methods private static void Recover(Exception e, int recoveryMode) { Console.ForegroundColor = ConsoleColor.DarkGreen; Console.WriteLine($"Recovered {e.Message} Recovery mode: {recoveryMode}"); Console.ResetColor(); } static void Recover(Exception e) { Recover(e, 2); } static void DoOperation(params object[] arguments) { if (arguments == null) { throw new ArgumentException($"{nameof(arguments)} cannot be null."); } if (arguments.Length > 3) { throw new ArgumentOutOfRangeException(nameof(arguments), $"{nameof(arguments)} is out of range. Upto 3 arguments are allowed."); } } static bool CanRecover(Exception ex) { ArgumentOutOfRangeException aoore = ex as ArgumentOutOfRangeException; return aoore != null; } static bool CanRecover(Exception ex, out int recoveryMode) { recoveryMode = 1; return false; } static bool LogException(Exception ex) { Console.ForegroundColor = ConsoleColor.Red; Console.WriteLine($"Exception occured: {ex}"); Console.ResetColor(); return false; } #endregion Helper Methods } } |