C# toString(＂X＂)，

C# toString("X")，

var guid = Guid.NewGuid();
foreach (var i in new string[] { "P", "N", "B", "P", "X" }) 
Console.WriteLine("{0}:{1}", i, guid.ToString(i).ToUpper());

P:(F944B769-E7E4-48AF-B70E-542626C02CB6)
N:F944B769E7E448AFB70E542626C02CB6
B:{F944B769-E7E4-48AF-B70E-542626C02CB6}
P:(F944B769-E7E4-48AF-B70E-542626C02CB6)
X:{0XF944B769,0XE7E4,0X48AF,{0XB7,0X0E,0X54,0X26,0X26,0XC0,0X2C,0XB6}}