How to Toggle String Case in .NET

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1. How to Toggle String Case in .Net Updated: 9 Feb 2011 StringBuilder mystring = new StringBuilder("AbCd");for (int i = 0; i < mystring.Length; i++){ char c = mystring[i]; mystring[i] = Char.IsLower(c) ? Char.ToUpper(c) : Char.ToLower(c);} C#, .NET	John Simmons / outlaw programmer
2. How to Toggle String Case in .Net Updated: 9 Feb 2011 This one should outperform both the other methods for longer strings because of the StringBuilder.string s = "AbCdEfGhI§$%&/()1234567890";var sb = new StringBuilder(s.Length);foreach (char c in s) sb.Append(char.IsUpper(c) ? char.ToLower(c) : char.ToUpper(c));s =... C#, .NET	Robert Rohde
3. How to Toggle String Case in .NET Updated: 14 Feb 2011 Test Page for both Algorithms: http://webinfocentral.com/resources/toggleCaseAlgorithm.aspx[^]Algorithm by Robert R.: protected string ToggleCaseByRobert(string s) { var sb = new StringBuilder(s.Length); foreach (char c in s) ... C#, .NET	DrABELL
4. How to Toggle String Case in .Net Updated: 11 Feb 2011 Interesting finding in regards to the Case Toggle Algorithm by Robert (see the following code snippet): protected string ToggleCaseByRobert(string s){ var sb = new StringBuilder(s.Length); foreach (char c in s) sb.Append(char.IsUpper(c) ? char.ToLower(c) :... C#, .NET	DrABELL
5. How to Toggle String Case in .NET Updated: 14 Feb 2011 Hi everybody-There is a question posted by Rod Kemp in regards to performance benchmarks used for both algorithms (see Alternate 4). The sample code snippet, pertinent to the "ToggleCaseByJohn" algorithm is as follows: DateTime dt = DateTime.Now; for (Int64 i = 0; i <... C#, .NET	DrABELL
6. How to Toggle String Case in .NET Updated: 17 Feb 2011 Couldn't resist: The following is a rewrite of Alternative 9, ToggleCaseHA()This is an unmanaged version which does direct manipulation of the input stringunsafe static string ToggleCaseUnmanaged(string str){ fixed(char* p = str) { for(int i=str.Length-1;i!=-1;--i)... C#, .NET	Michael B. Hansen
7. How to Toggle String Case in .NET Updated: 22 Feb 2011 Following two Toggle Case Algorithms, implemented as "pure" .NET solution (no "unsafe" coding technique, all managed code) demonstrate the best performance, tested against a variety of text strings, containing: ASCII, Unicode, all Low case, all Upper case, long numeric strings (refer to the test... C#, .NET	DrABELL
8. How to Toggle String Case in .NET Updated: 5 Mar 2011 This code is 27% faster on my machine (.NET 4/AnyCPU on a 64bit i5 processor) for the Unicode test than the Ayoola/Bell algorithm.No unsafe code (in fact was 18% faster than the unsafe version as posted) and works with Unicode.public static string ToggleCase_SimmoTech(string s){ ... C#, .NET	SimmoTech
9. How to Toggle String Case in .NET Updated: 5 Mar 2011 Two more goes and then I'm done. (Wish I could get a job doing this kind of stuff! Wish I could get a job!)This is similar to my previous attempt but Reflector showed how ToLower() and ToUpper() are implemented and we can save some time by caching the CurrentCulture.TextInfo which saves... C#, .NET	SimmoTech
10. How to Toggle String Case in .NET Updated: 7 Dec 2011 For VB.NET users:Public Function ToggleCase(input As String) As String Dim result As String = String.Empty Dim inputArray As Char() = input.ToCharArray() For Each c As Char In inputArray If Char.IsLower(c) Then result += [Char].ToUpper(c) Else result +=... C#, .NET	Jαved
11. How to Toggle String Case in .NET Updated: 15 Feb 2011 This does the same. (I'm not sure it's better, but I'm a fan of this style) :)static string toggle(string t){ return (from c in t select new string(Char.IsLower(c) ? Char.ToUpper(c) : Char.ToLower(c), 1)).Aggregate((a, b) => a += b);}much better performance than stringbuilder... C#, .NET	cechode
12. How to Toggle String Case in .NET Updated: 14 Feb 2011 Of the 5 alternatives...somehow the obvious suggestion of dropping the ToUpper() after calling IsUpper() (or ToLower/IsLower) was missed.char.IsUpper(c) ? char.ToLower(c) : char.ToUpper(c)to become...char.IsUpper(c) ? char.ToLower(c) : cThis saves half call to a method per character "on... C#, .NET	Nathan J Bolstad
13. How to Toggle String Case in .NET Updated: 14 Feb 2011 Shows how to toggle the contents of a string from upper case to lower, or vice versa C#, .NET	Manas Bhardwaj
14. How to Toggle String Case in .NET Updated: 17 Feb 2011 Using the .NET profiler, I compared ToggleCaseByRobertToggleCaseByJohnand my new one given below: static string ToggleCaseByCeChode(string s) { char[] chars = s.ToCharArray(); for (int i = 0; i < chars.Length; i++) { ... C#, .NET	cechode
15. How to Toggle String Case in .NET Updated: 8 Mar 2011 Several of the answers here lack fallbacks for Unicode.static string ToggleCaseHA(string str) { char[] chs = str.ToCharArray(); for (int i = chs.Length - 1; i >= 0; i--) { char ch = chs[i]; char foo = (char)(ch & ~0x20); if ((foo >= 0x41 && foo <= 0x5a)... C#, .NET	Henry.Ayoola
16. How to Toggle String Case in .NET Updated: 21 Feb 2011 public static string ToggleCase(string s){ char[] ar = s.ToCharArray(); for(int i = 0; i < ar.Length; ++i) ar[i] = char.IsLower(ar[i]) ? char.ToUpper(ar[i]) : char.ToLower(ar[i]); return new string(ar); } C#, .NET	nedel
17. How to Toggle String Case in .NET Updated: 23 Feb 2011 Hi,Don`t know how to test its speed, but this does the trick and it also handles unicode. My aproach was to test for casing the least ammount of times as possible, I didn`t figure out how to group accented letters, for those it does it one at a time, so there is still room for improvement.... C#, .NET	Rogenator
18. How to Toggle String Case in .NET Updated: 23 Feb 2011 I think if you just want to toggle the case of letters in some string, you don't need any special algorithms and sophisticated methods.In fact, no matter what method you select, you must remember that POINTER is the fastest runner.After reading all methods submitted above, I should say that... C#, .NET	Kevinyou
19. How to Toggle String Case in .NET Updated: 24 Feb 2011 What about this :) string ToggleStringCase(string strToToggle){ StringBuilder sb = new StringBuilder(); foreach(char ch in strToToggle.ToCharArray()) { if((int)ch>=65&&(int)ch<91) { sb.Append((char)((int)ch+32)); } else... C#, .NET	code in play
20. How to Toggle String Case in .NET Updated: 23 Mar 2011 And yet another ...5% slower ... than the fastest to date -> SimmoTech's v2,(an awesome piece of righteously parsimonious code).85% less filling ... the diet version -> 44 vs 256 bytes(.Net v2 and above)private const int AddressBitsPerUnit = 5;private const int BitsPerElement =... C#, .NET	MacMaverick
21. How to Toggle String Case in .NET Updated: 8 Dec 2011 A whole lot less code and a lot easier to do.public static string ToggleCase(this string str){ if (string.IsNullOrEmpty(str)) return str; return string.Join("", (from i in str select (char.IsLetter(i) ? ... C#, .NET	Daniel Gidman
22. How to Toggle String Case in .NET Updated: 14 Jun 2012 This is an alternative for "How to Toggle String Case in .NET" C#, .NET	Andreas Gieriet