using System;
using System.Text.RegularExpressions;
public class Example
{
public static void Main()
{
string pattern = @"(?:[^a-zA-Z0-9]*[a-zA-Z0-9]){3}";
string input = @"+++++' 'asd'''''''''''sdsdsdsdsdsddddddddddddddddddddddddddddddddd'''' fdfdfdfdfddfdfdfdfdfdfdfdfdfdfdfdf''sssdssssssssssssssssssssssssss'''''sd''''''' d
'''''''''''''sd'' sfdasdasd dsa sdk' d' ddaf 3f0 sc'ddd'_0_c_8_'' 9 9d 'c'ddd'_0_csdf
as 0a
_0_c_sdf8_
K9Jk0-asd
L________f______________3j
]\[][]\[";
Match m = Regex.Match(input, pattern);
Console.WriteLine("'{0}' found at index {1}", m.Value, m.Index);
}
}
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