You could use positive lookahead and lookbehind also,
string val = "name='40474740-1e40-47ce-aeba-ebd1eb1630c0'";
Match match = Regex.Match(val, @"(?<=')[^']*(?=')");
if (match.Success)
{
string yourValue = match.Groups[0].Value;
Console.WriteLine(yourValue);
}