using System;
using System.Text.RegularExpressions;
public class Example
{
public static void Main()
{
string pattern = @"((?:[ -$&(-[\]-~]|([%'\\])\2)*(%(\d+\$)?[-+\s0#]?(\d+|\*)?(\.\d+)?[bt]?[diuoxXfeEgGcs]+)+(?:(?!(?:[ -$&(-[\]-~]|([%'\\])\7)*(?:%(?:\d+\$)?[-+\s0#]?(?:\d+|\*)?(?:\.\d+)?[bt]?[diuoxXfeEgGcs]+)+)(?:[ -$&(-[\]-~]|([%'\\])\8)*)?)
";
string substitution = @"IMAGE REMOVED FROM CHROME\r\n";
string input = @"Color %s, we are looking for %%02droids %% number1 %d, number2 %05d, hex %#x, float %5.2f, unsigned value %u.
I wanted to also add the ability to capture ""any printable text characters besides %, ' and \, unless these characters appear exactly twice"". This needs to be captured both before the initial % and after the conversion character.
any printable character: [ -~]
besides %, ' and \: (?![\\%'])
these characters appear exactly twice: ( §§§§ |'{2}|\\{2}|%{2}) (§ = placeholder)
I am having a problem with the ""unless"", that is, getting the negative look-ahead to discard single occurrences but allow double occurrences of the specified characters.
Color %s, number1 %d, number2 %05d, hex %#x, float %5.2f, unsigned value %u.
| | | | | | |";
RegexOptions options = RegexOptions.Multiline | RegexOptions.IgnoreCase | RegexOptions.IgnorePatternWhitespace;
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