c#怎样将char转为byte

byte[] bts = BitConverter.GetBytes ('a');

有两张方法：
方法一:
//字符串转byte
string StringMessage = "How Are you?";
Console.WriteLine("{0}", StringMessage);
System.Text.ASCIIEncoding ASCII = new System.Text.ASCIIEncoding();
Byte[] BytesMessage = ASCII.GetBytes(StringMessage);
//byte转字符串
Byte[] BytesMessage;
System.Text.ASCIIEncoding ASCII = new System.Text.ASCIIEncoding();
String StringMessage = ASCII.GetString( BytesMessage );

方法二:
//字符串转UTF-8 byte
string StringMessage = "Hello World How Are you? Pi /u03C0 Yen /uFFE5";
System.Text.UTF8Encoding UTF8 = new System.Text.UTF8Encoding();
Byte[] BytesMessage = UTF8.GetBytes(StringMessage);
//UTF-8 byte 转字符串
Byte[] BytesMessage;
System.Text.UTF8Encoding UTF8 = new System.Text.UTF8Encoding();
String StringMessage = UTF8.GetString( BytesMessage );