using System;
using System.Text.RegularExpressions;
public class Test
{
public static void Main()
{
string lnk = "asdf %12aa22bb33% dafg";
string resultString = Regex.Match(lnk, @"%([0-9a-zA-Z]{10})%").Groups[1].Value;
Console.WriteLine(resultString);
}
}
dXNpbmcgU3lzdGVtOwp1c2luZyBTeXN0ZW0uVGV4dC5SZWd1bGFyRXhwcmVzc2lvbnM7CgpwdWJsaWMgY2xhc3MgVGVzdAp7CglwdWJsaWMgc3RhdGljIHZvaWQgTWFpbigpCgl7CgkJc3RyaW5nIGxuayA9ICJhc2RmICUxMmFhMjJiYjMzJSBkYWZnIjsKICAgICAgICAgICAgICAgIHN0cmluZyByZXN1bHRTdHJpbmcgPSBSZWdleC5NYXRjaChsbmssIEAiJShbMC05YS16QS1aXXsxMH0pJSIpLkdyb3Vwc1sxXS5WYWx1ZTsKICAgICAgICAgICAgICAgIENvbnNvbGUuV3JpdGVMaW5lKHJlc3VsdFN0cmluZyk7Cgl9Cn0=