阅读下面的程序, 分析代码是否能够编译通过,如果能编译通过,请列出运行的结果。否则请说明编译失败的原因。 代码一: public class Test01 { public static void Main(string[] args) { byte b = 3; b = b + 4; Console.WriteLine("b=" + b); } } 代码二: public class Test02 { public static void Main(string[] args) { int x = 12; { int y = 96; Console.WriteLine("x is " + x); Console.WriteLine("y is " + y); } y = x; Console.WriteLine("x is " + x); } } 代码三: public class Test03 { public static void Main(string[] args) { int x = 4, j = 0; switch (x) { case 1: j++; case 2: j++; case 3: j++; case 4: j++; case 5: j++; default: j++; } Console.WriteLine(j); Console.ReadKey(); } } 代码四: public class Test04 { public static void Main(string[] args) { int n = 9; while (n > 6) { Console.WriteLine(n); n--; } } }