// Copyright (c) AlphaSierraPapa for the SharpDevelop Team (for details please see \doc\copyright.txt) // This code is distributed under MIT X11 license (for details please see \doc\license.txt) using System; using System.Collections.Generic; public static class YieldReturn { public static IEnumerable SimpleYieldReturn() { yield return "A"; yield return "B"; yield return "C"; } public static IEnumerable YieldReturnInLoop() { for (int i = 0; i < 100; i++) { yield return i; } } public static IEnumerable YieldReturnWithTryFinally() { yield return 0; try { yield return 1; } finally { Console.WriteLine("Finally!"); } yield return 2; } public static IEnumerable YieldReturnWithNestedTryFinally(bool breakInMiddle) { Console.WriteLine("Start of method - 1"); yield return "Start of method"; Console.WriteLine("Start of method - 2"); try { Console.WriteLine("Within outer try - 1"); yield return "Within outer try"; Console.WriteLine("Within outer try - 2"); try { Console.WriteLine("Within inner try - 1"); yield return "Within inner try"; Console.WriteLine("Within inner try - 2"); if (breakInMiddle) yield break; Console.WriteLine("End of inner try - 1"); yield return "End of inner try"; Console.WriteLine("End of inner try - 2"); } finally { Console.WriteLine("Inner Finally"); } Console.WriteLine("End of outer try - 1"); yield return "End of outer try"; Console.WriteLine("End of outer try - 2"); } finally { Console.WriteLine("Outer Finally"); } Console.WriteLine("End of method - 1"); yield return "End of method"; Console.WriteLine("End of method - 2"); } public static IEnumerable YieldReturnWithTwoNonNestedFinallyBlocks(IEnumerable input) { // outer try-finally block foreach (string line in input) { // nested try-finally block try { yield return line; } finally { Console.WriteLine("Processed " + line); } } yield return "A"; yield return "B"; yield return "C"; yield return "D"; yield return "E"; yield return "F"; // outer try-finally block foreach (string line in input) yield return line.ToUpper(); } public static IEnumerable> YieldReturnWithAnonymousMethods1(IEnumerable input) { foreach (string line in input) { yield return () => line; } } public static IEnumerable> YieldReturnWithAnonymousMethods2(IEnumerable input) { foreach (string line in input) { string copy = line; yield return () => copy; } } }