using System;
using System.Text.RegularExpressions;
public class Example
{
public static void Main()
{
string pattern = @"([0-9]{11}).+?(\s*[0-9].+)";
string substitution = @"$1xxxxxxxxxxxxxxxxxxxx$2";
string input = @"01234567890Alice Stone 3978 Smith st...
01234567890Alice Stone3978 Smith st...";
RegexOptions options = RegexOptions.Multiline;
Regex regex = new Regex(pattern, options);
string result = regex.Replace(input, substitution);
}
}
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for C#, please visit: https://msdn.microsoft.com/en-us/library/system.text.regularexpressions.regex(v=vs.110).aspx