String 和 byte[] 轉換

 

String 類型轉成 byte[]：

   1: byte [] byteArray  =  System.Text.Encoding.Default.GetBytes ( str );

byte[]轉成string：

   1: string  str  =  System.Text.Encoding.Default.GetString ( byteArray );

其它編碼方式，如System.Text.UTF8Encoding，System.Text.UnicodeEncoding。
例如：
string 類型轉成ASCII byte[]：( "01"轉成byte[] = new byte[] {0x30, 0x31} )

   1: byte [] byteArray  =  System.Text.Encoding.ASCII.GetBytes ( str );

ASCII byte[] 轉成string：（byte[] = new byte[]{ 0x30, 0x31}轉成"01"）

   1: string  str  =  System.Text.Encoding.ASCII.GetString ( byteArray );

byte[] 轉成原16進制格式的string，例如0xae00cf,轉換成"ae00cf"；new byte[]{ 0x30, 0x31}轉成"3031":

   1: public static string ToHexString ( byte[] bytes ) // 0xae00cf => "AE00CF "

   2: {

   3:              string hexString = string.Empty;

   4:              if ( bytes != null )

   5:             {

   6:                  StringBuilder strB = new StringBuilder ();

   7:                  for ( int i = 0; i < bytes.Length; i++ )

   8:                 {

   9:                      strB.Append ( bytes[i].ToString ( "X2" ) );

  10:                 }

  11:                  hexString = strB.ToString ();

  12:             }

  13:              return hexString;

  14:   } 

16進制格式的string轉成byte[]，例如, "ae00cf"轉換成0xae00cf，長度縮減一半；"3031"轉成new byte[]{ 0x30, 0x31}:

   1: public static byte[] GetBytes(string hexString, out int discarded)

   2:  {

   3:              discarded = 0;

   4:              string newString = "";

   5:              char c;

   6:              // remove all none A-F, 0-9, characters

   7:              for (int i=0; i<hexString.Length; i++)

   8:             {

   9:                  c = hexString[i];

  10:                  if (IsHexDigit(c))

  11:                      newString += c;

  12:                  else

  13:                      discarded++;

  14:             }

  15:              // if odd number of characters, discard last character

  16:              if (newString.Length % 2 != 0)

  17:             {

  18:                  discarded++;

  19:                  newString = newString.Substring(0, newString.Length-1);

  20:             }

  21:  

  22:              int byteLength = newString.Length / 2;

  23:              byte[] bytes = new byte[byteLength];

  24:              string hex;

  25:              int j = 0;

  26:              for (int i=0; i<bytes.Length; i++)

  27:             {

  28:                 hex = new String(new Char[] {newString[j], newString[j+1]});

  29:                  bytes[i] = HexToByte(hex);

  30:                  j = j+2;

  31:             }

  32:              return bytes;

  33:  }