Use regular to replace word
using System; using System.Text.RegularExpressions; class RegexSubstitution { public static void Main() { string testString1 = "a b c stars *****"; Regex testRegex1 = new Regex( @"\d" ); Console.WriteLine( "Original string: " + testString1 ); Console.WriteLine( "Every word replaced by \"word\": " + Regex.Replace( testString1, @"\w+", "word" ) ); } }