public static string LengthDecode(this string str)
{
if (str.IsNullOrEmpty() || str.Length < 4)
{
return(null);
}
string value = str.GetFirst(4);
Int32 length = Int32Ex.FromStringValue(value);
if (length == -1)
{
return(null);
}
if (length == 0)
{
return("");
}
if (str.Length < length + 4)
{
return(null);
}
return(str.RemoveFirst(4).GetFirst(length));
}
public static byte[] ToByteArrayFromString(string str)
{
if (str.IsNullOrEmpty())
{
return(null);
}
int mod4 = str.Length % 4;
if (mod4 > 0)
{
str += new string('*', 4 - mod4);
}
byte[] data = Convert.FromBase64String(str);
if (data.Length < 4)
{
return(null);
}
int length = Int32Ex.FromBytes(data);
if (length == 0)
{
return(new byte[0]);
}
if (length < 0 || data.Length < 4 + length)
{
return(null);
}
return(data.Skip(4).Take(length).ToArray());
}
public static string ToStringValue(Int32 value)
{
byte[] bytes = Int32Ex.ToBytes(value);
string result = string.Empty;
foreach (byte b in bytes)
{
result += (char)b;
}
return(result);// System.Text.Encoding.UTF8.GetString(bytes);
}
/// <summary>
/// encodes string into [length][data] array
/// </summary>
/// <param name="str"></param>
/// <returns></returns>
public static byte[] GetBytesEncoded(this string str)
{
if (str == null)
{
return(null);
}
List <byte> buff = new List <byte>();
buff.AddRange(str.GetBytes());
buff.AddToStart(Int32Ex.ToBytes(buff.Count)); //save mode
return(buff.ToArray());
}
/// <summary>
/// Encodes length into array - encodes bytes into [length][data] array
/// </summary>
/// <param name="data"></param>
/// <returns></returns>
public static byte[] EncodeWithLength(this byte[] data)
{
if (data == null)
{
return(null);
}
List <byte> buff = new List <byte>();
buff.AddRange(Int32Ex.ToBytes(data.Length));
buff.AddRange(data);
return(buff.ToArray());
}
public static Int32 FromStringValue(string value)
{
if (value.IsNullOrEmpty() || value.Length < 4)
{
throw new Exception("value is to small to contain any value");
}
byte[] bytes = new byte[4];
for (int i = 0; i < bytes.Length; i++)
{
bytes[i] = (byte)value[i];
}
//byte[] bytes = System.Text.Encoding.UTF8.GetBytes(value);
return(Int32Ex.FromBytes(bytes));
}
public static string LengthEncode(this string str)
{
Int32 length;
if (str == null)
{
length = -1;
}
else
{
length = str.Length;
}
str = Int32Ex.ToStringValue(length) + str;
return(str);
}
/// <summary>
/// decodes bytes into string from [some offset bytes][length][data][other bytes] array
/// </summary>
/// <param name="array"></param>
/// <param name="offset"></param>
/// <returns></returns>
public static string GetStringDecoded(this byte[] array, int offset)
{
if (array == null)
{
return(null);
}
int length = Int32Ex.FromBytes(array, offset);
if (length < 0 || length > array.Length + 4 + offset)
{
return(null);
}
return(stringEx.GetString(array.SubArray(4 + offset, length)));
}
/// <summary>
/// Decodes array using encoded length - decodes bytes into bytes from [some offset bytes][length][data][other bytes] array
/// </summary>
/// <param name="array"></param>
/// <param name="offset"></param>
/// <returns></returns>
public static byte[] DecodeWithLength(this byte[] array, int offset)
{
if (array == null || array.Length < 4)
{
return(null);
}
int length = Int32Ex.FromBytes(array, offset);
if (length < 0 || length > array.Length + 4 + offset)
{
return(null);
}
else if (length == 0)
{
return(new byte[0]);
}
return(array.SubArray(4 + offset, length));
}
public static string ToStringFromByteArray(byte[] bytes)
{
if (bytes == null)
{
return(null);
}
byte[] length = Int32Ex.ToBytes(bytes.Length);
List <byte> data = new List <byte>();
data.AddRange(length);
data.AddRange(bytes);
while (data.Count % 8 != 0)
{
data.Add(0);
}
return(Convert.ToBase64String(data.ToArray()));
}
