Last index

Question

Is it possible to use LastIndexOf to find the last index of a specific character before another specified character?

Say I had the string 'This is my string', and I wanted to find the last index of the letter 'i' before 'my', how would this be used?

Thanks in advance for any help

Vulpes · Answer

Going back to the way you originally posed this question you might find it easier to get the indices of all the operators 'in one go' using a regular expression: using System; using System.Text.RegularExpressions; class Program { static void Main() { string expression = 4+2.345/3; string regex = @(\+|-|\*|/); // need to escape + and * as regex metacharacters MatchCollection ops = Regex.Matches(expression regex); foreach(Match op in ops) { Console.WriteLine({0} : {1} op.Index op.Value); } Console.ReadKey(); } } To use LastIndexOf you'd need to use this overload ( http://msdn.microsoft.com/en-us/library/1tw91fa3.aspx ) which starts the search at a specified position.