/// <summary>
/// 清除缓存区
/// </summary>
public void Clear()
{
this._header = null;
this._extend = null;
Array.Clear(this._extend, 0, _extend.Length);
Array.Clear(this._mask, 0, _extend.Length);
Array.Clear(this._content, 0, _extend.Length);
}
/// <summary>
/// 构造函数
/// </summary>
/// <remarks>主要用于解析接收数据</remarks>
public DataFrame(byte[] buffer, ref int offset)
{
//格式化帧头
_header = new DataFrameHeader(buffer);
//填充扩展长度字节
if (_header.Length == 126)
{
_extend = new byte[2];
Buffer.BlockCopy(buffer, 2, _extend, 0, 2);
}
else if (_header.Length == 127)
{
_extend = new byte[8];
Buffer.BlockCopy(buffer, 2, _extend, 0, 8);
}
//是否有掩码
if (_header.HasMask)
{
_mask = new byte[4];
Buffer.BlockCopy(buffer, _extend.Length + 2, _mask, 0, 4);
}
//消息体 <126
if (_extend.Length == 0)
{
_content = new byte[_header.Length];
Buffer.BlockCopy(buffer, _extend.Length + _mask.Length + 2, _content, 0, _content.Length);
offset = 6;
}
else if (_extend.Length == 2)//<=65535
{
ulong PlayLenth = (UInt16)(buffer[2] << 8 | buffer[3]);
_content = new byte[PlayLenth];
Buffer.BlockCopy(buffer, _extend.Length + _mask.Length + 2, _content, 0, _content.Length);
offset = 8;
}
else
{
// UInt64 len = BitConverter.ToUInt64(buffer, 2);
byte[] uInt64Bytes = new byte[8];
for (int i = 0; i < 8; i++)
{
uInt64Bytes[i] = buffer[9 - i];
}
UInt64 len = BitConverter.ToUInt64(uInt64Bytes, 0);
_content = new byte[len];
Buffer.BlockCopy(buffer, _extend.Length + _mask.Length + 2, _content, 0, _content.Length);
offset = 14;
}
//如果有掩码，则需要还原原始数据
if (_header.HasMask)
{
_content = Mask(_content, _mask);
}
}
/// <summary>
/// 构造函数
/// </summary>
/// <remarks>主要用于发送封装数据</remarks>
public DataFrame(byte[] content, bool isText = false)
{
_content = content;
sbyte opcode = 0;
if (isText)
{
opcode = OpCode.Text;
}
else
{
opcode = OpCode.Binary;
}
int length = _content.Length;
if (length < 126)
{
_extend = new byte[0];
_header = new DataFrameHeader(true, false, false, false, opcode, false, length);
}
else if (length < 65536)
{
_extend = new byte[2];
_header = new DataFrameHeader(true, false, false, false, opcode, false, 126);
_extend[0] = (byte)(length / 256);
_extend[1] = (byte)(length % 256);
}
else
{
_extend = new byte[8];
_header = new DataFrameHeader(true, false, false, false, opcode, false, 127);
int left = length;
int unit = 256;
for (int i = 7; i > 1; i--)
{
_extend[i] = (byte)(left % unit);
left = left / unit;
if (left == 0)
{
break;
}
}
}
}