When we need to search a string for every occurrence of a specific string along with case consideration we can use the IndexOf or IndexOfAny in a loop. This helps to determine how many occurrences of a character or string exist as well as their locations within the string.
Example Code to find each occurrence of a string in another string using a case-sensitive search:
using System.Collections; using System.Collections.Generic; static class CharStrExtMethods { public static int[] FindAll(this string matchStr, string searchedStr, int startPos) { int foundPos = -1; // -1 represents not found. int count = 0; List<int> foundItems = new List<int>( ); do { foundPos = searchedStr.IndexOf(matchStr, startPos, StringComparison. Ordinal); if (foundPos > -1) { startPos = foundPos + 1; count++; foundItems.Add(foundPos); Console.WriteLine("Found item at position: " + foundPos. ToString( )); } } while (foundPos > -1 && startPos < searchedStr.Length); return ((int[])foundItems.ToArray( )); } }
Example of FindAll extension method called with the following parameters:
string data = "mad"; int[] allOccurrences = data.FindAll("Themadmanisinthemadhouse", 0);
