In this post, we will see some interesting methods to use with String.
HOW TO REVERSE A STRING
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 | public static string ReverseWord( string strInput) { StringBuilder resultStr = new StringBuilder(); int startI = strInput.Length - 1; for ( int i = startI; i >= 0; i--) { resultStr.Append(strInput[i]); } return resultStr.ToString(); } static void Main( string [] args) { string strInput = "Damiano Abballe" ; Console.WriteLine(strInput); Console.WriteLine(ReverseWord(strInput)); } |
HOW TO REVERSE THE ORDER OF WORDS IN A GIVEN STRING
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 | public static string ReverseString( string strInput) { StringBuilder resultStr = new StringBuilder(); var arrayInput = strInput.Split( ' ' ); int startI = arrayInput.Length - 1; for ( int i = startI; i >= 0; i--) { resultStr.Append($ "{arrayInput[i]} " ); } return resultStr.ToString().Trim(); } static void Main( string [] args) { string strInput = "Welcome to my blog" ; Console.WriteLine(strInput); Console.WriteLine(ReverseString(strInput)); } |
HOW TO COUNT THE OCCURRENCE OF EACH CHARACTER IN A STRING
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 | public static void CountCharacters( string strInput) { // With a Regular Expressions, we will remove all space strInput = Regex.Replace(strInput.ToUpper(), @"\s+" , "" ); var countChar = new Dictionary< char , int >(); int endI = strInput.Length - 1; int oldCount = 1; for ( int i = 0; i <= endI; i++) { if (countChar.ContainsKey(strInput[i])) { oldCount = countChar[strInput[i]]; countChar[strInput[i]] = oldCount + 1; } else { countChar.Add(strInput[i], 1); } } // Display the Counter for ( int i = 0; i < countChar.Count; i++) { Console.WriteLine($ "Character: {countChar.ElementAt(i).Key}, Count: {countChar.ElementAt(i).Value}" ); } } static void Main( string [] args) { string strInput = "hello world" ; CountCharacters(strInput); } |
HOW TO FIND ALL POSSIBLE SUBSTRING OF A GIVEN STRING
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 | public static void FindSubstring( string strInput) { int currentStart = 0; int endI = strInput.Length - 1; int endSubstring = 1; StringBuilder result = new StringBuilder(); while (currentStart <= strInput.Length - 1) { for ( int i = currentStart; i <= endI; i++) { result.Append($ "{strInput.Substring(currentStart, endSubstring)}," ); endSubstring++; } endSubstring = 1; currentStart++; } Console.WriteLine(result.ToString()); } static void Main( string [] args) { string strInput = "abcd" ; Console.WriteLine(strInput); FindSubstring(strInput); } |
HOW TO REMOVE DUPLICATE CHARACTERS FROM A STRING
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 | public static void RemoveDuplicareCharacters( string inputString) { StringBuilder result = new StringBuilder(); HashSet< char > noDuplicate = new HashSet< char >(); foreach ( char item in inputString) { if (noDuplicate.Add(item)) { result.Append(item); } } Console.WriteLine(result.ToString()); } static void Main( string [] args) { string inputStr = "Coffee" ; Console.WriteLine(inputStr); RemoveDuplicareCharacters(inputStr); } |