obex 的小用

　（一）、获取附近可用红外设备的信息
　　在这个示例中，我获取红外设备通过IrDAClient的DiscoverDevices方法实现，该方法以IrDADeviceInfo类型的对象数组返回附近可用红外设备的相关信息。这个方法唯一的参数表示如果附近有许多红外设备时，最多收集多少个设备的信息。
　　示例代码如下：

Dim taobjIrDADeviceInfo() As Sockets.IrDADeviceInfo
Dim tobjIrDAClient As New Sockets.IrDAClient
’开始检索附近的红外设备并加入到列表中，最多只搜索7个设备
taobjIrDADeviceInfo = tobjIrDAClient.DiscoverDevices(7)
　在得到的IrDADeviceInfo类型的变量有三个有用的属性，你可根据这些属性的值给用户提示，以便由用户选择应连接到那一个红外设备上：
　　DeviceID 获取红外设备标识符，在连接红外设备中使用
　　DeviceName 获取红设备名称。
　　Hints 获取设备的类型，例如是红外手机还是红外PDA之类的说明
　　（二）、用IrDAClient对象实现红外连接及数据发送
　　IrDAClient和一般的网络连接对象的使用很相似，使用的基本步骤如下：  
　　1）、先使用connect方法连接指定的红外设备，这个方法需要一个IrDAEndPoint对象作为参数（这个对象指定需连接的红外设备，以及连接到红外设备提供的指定服务上）
　　示例：

Dim tobjIrDAClient As New Sockets.IrDAClient
’ni_objIrDADeviceInfo是上文介绍的IrDADeviceInfo对象，以下语句的含义就是连接到’DeviceID指定的红外设备上，这个设备提供OBEX服务。
Dim tobjIrDAEndPoint As New IrDAEndPoint(ni_objIrDADeviceInfo.DeviceID, "OBEX")
Try
tobjIrDAClient.Connect(tobjIrDAEndPoint)
Catch ex As Exception
MessageBox.Show("IrDA Socket Connect 状态失败")
End Try
　　2）、连接成功后就可以使用IrDAClient对象的GetStream 方法获得基础数据流，并利用流Read/Write方法实现数据传输的接收/发送。
　　示例：两个方法的第一个参数都是一个字节数组
　　数据发送：tobjIrDAClient.GetStream.Write(tabytTempa, 0, tabytTempa.Length)
　　数据接收：tobjIrDAClient.GetStream.Read(tabytReceiveBuffer, 0, 7)
　　3）、完成所有通信后使用流以及IrDAClient的Close方法 关闭连接。
　　示例：tobjIrDAClient.GetStream.Close()
　　　　　tobjIrDAClient.Close()
　　（三）完整实现代码
　 　其实红外操作在net中实现就是这么简单，不过困难的是对OBEX协议的解释，基于代码重用的原则，我的程序主框架有两个基础类， clsIrDAOBEXOperator封装了文件发送的方法，方法中调用另一个类clsOBEXHeaders，这个类主门用来构建obex协议需要的 数据包。代码如下，其中已包括必要的注释：
　　clsIrDAOBEXOperator.VB的代码（代码中fnSendFileToIrDADevice是向红外设备发送文件的方法，它的第一个参数是代表红外设备的IrDADeviceInfo对象，第二个参数就是要发送的文件名），：

Imports System.Net
Imports System.Net.Sockets
Public Class clsIrDAOBEXOperator
’OBEX常数
Public Const cOBEX_VERSION As Byte = &H10
Public Const cOBEX_CONNECTFLAGS As Byte = &H0
Public Const cOBEX_CONNECT As Byte = &H80
Public Const cOBEX_DISCONNECT As Byte = &H81
Public Const cOBEX_PUT As Byte = &H2
Public Const cOBEX_NAME As Byte = &H1
Public Const cOBEX_PUT_FINAL As Byte = &H82
Public Const cOBEX_LENGTH As Byte = &HC3
Public Const cOBEX_BODY As Byte = &H48
Public Const cOBEX_END_OF_BODY As Byte = &H49
Public Const cOBEX_CONTINUE As Byte = &H90
Public Const cOBEX_SUCCESS As Byte = &HA0
’向外界公布可直接修改的变量
Public m_i32OBEXMAXSendBufferLen As Int32 = 255
Public m_i32OBEXMAXReceiveBufferLen As Int32 = 1024
Public m_i32OBEXMAXPacketSize As Int16 = &H808
’将一个16位整数转为2个字节的数组,并存入参数中指定索引开始的字节数组处(低位字在低字节，高位字在高字节）
Private Function fnInt16ToByteArray(ByVal ni_i16Convert As Int16, ByRef ni_abytDest() As Byte, ByVal ni_i32StartIndex As Int32) As Boolean
ni_abytDest(ni_i32StartIndex) = ni_i16Convert And &HFF
ni_abytDest(ni_i32StartIndex + 1) = ni_i16Convert >> 8
End Function
’将一个16位整数转为2个字节的数组,并存入参数中指定索引开始的字节数组处
Private Function fnInt16ToByteArrayLowByteToHightPosition(ByVal ni_i16Convert As Int16, ByRef ni_abytDest() As Byte, ByVal ni_i32StartIndex As Int32) As Boolean
ni_abytDest(ni_i32StartIndex + 1) = ni_i16Convert And &HFF
ni_abytDest(ni_i32StartIndex) = ni_i16Convert >> 8
End Function
’将一个32位整数转为4个字节的数组,并存入参数中指定索引开始的字节数组处
Private Function fnInt32ToByteArrayLowByteToHightPosition(ByVal ni_i32Convert As Int16, ByRef ni_abytDest() As Byte, ByVal ni_i32StartIndex As Int32) As Boolean
Dim ti32Tempa As Int32 = ni_i32Convert
ni_abytDest(ni_i32StartIndex + 3) = ni_i32Convert And &HFF
ni_abytDest(ni_i32StartIndex + 2) = (ni_i32Convert And &HFF00) >> 8
ni_abytDest(ni_i32StartIndex + 1) = (ni_i32Convert And &HFF0000) >> 16
ni_abytDest(ni_i32StartIndex) = (ti32Tempa And &HFF000000) >> 24
End Function
’将本设备中指定的文件传到指定的设备中去
Public Function fnSendFileToIrDADevice(ByVal ni_objIrDADeviceInfo As IrDADeviceInfo, _
ByVal ni_strFilePath As String) As Boolean
’ni_objIrDADeviceInfo：指定红外设备的IrDAInfo结构
’ni_strFilePath:要传输的文件路径
’返回值：成功返回true
Dim tobjIrDAClient As New Sockets.IrDAClient
Dim tobjIrDAEndPoint As New IrDAEndPoint(ni_objIrDADeviceInfo.DeviceID, "OBEX")
Dim tabytSendBuffer(m_i32OBEXMAXSendBufferLen * 2) As Byte
Dim tabytReceiveBuffer(m_i32OBEXMAXReceiveBufferLen) As Byte
Dim tblnTemp As Boolean
Dim ti32Tempa As Int32, ti32TempB As Int32, tieTempC As Int32
Dim tbytTempa As Byte
Dim ti32LoopA As Int32
Dim tobjBinaryReader As IO.BinaryReader
Dim tobjFileStream As IO.FileStream
Dim tabytTempa() As Byte, tabytTempb() As Byte, tabytTempC() As Byte, tabytTempD() As Byte
Dim tabytTempE() As Byte
Dim tobjOBEX_HEADERS As New clsOBEXHeaders
Dim ti32SendPackageSpare As Int32 ’保存最大发送包数组-当前数据后的剩余空间
Dim tobjFileInfo As IO.FileInfo
tobjFileInfo = New IO.FileInfo(ni_strFilePath)
Try
Try
tobjIrDAClient.Connect(tobjIrDAEndPoint)
Catch ex As Exception
MessageBox.Show("IrDA Socket Connect 状态失败")
Return False
End Try
’创建一个最简单的连接信息
tabytTempa = tobjOBEX_HEADERS.fnCreateConnectHeaderRequest(, , , m_i32OBEXMAXPacketSize)
Try
tobjIrDAClient.GetStream.Write(tabytTempa, 0, tabytTempa.Length)
tobjIrDAClient.GetStream.Flush()
Catch ex As Exception
MessageBox.Show("OBEX_CONNECT信息发送失败")
Application.DoEvents()
Return False
End Try
If tobjIrDAClient.GetStream.CanRead = True Then
Try
tobjIrDAClient.GetStream.Read(tabytReceiveBuffer, 0, 7)
Catch ex As Exception
MessageBox.Show("接收OBEX_CONNECT响应消息失败")
Return False
End Try
If tabytReceiveBuffer(0)  cOBEX_SUCCESS Then
MessageBox.Show("OBEX_CONNECT没接收到相应的响应")
Return False
End If
End If
’发送put包
’Name包
tabytTempa = tobjOBEX_HEADERS.fnCreateNameHeader(IO.Path.GetFileName(ni_strFilePath))
ti32Tempa = tabytTempa.Length
’lenght包
tabytTempb = tobjOBEX_HEADERS.fnCreateLengthHeader(tobjFileInfo.Length)
ti32TempB = tabytTempb.Length
’时间
tabytTempC = tobjOBEX_HEADERS.fnCreateTimeHeaderISO(Now)
ReDim Preserve tabytTempa(tabytTempa.Length + tabytTempb.Length + tabytTempC.Length)
tabytTempb.CopyTo(tabytTempa, ti32Tempa)
tabytTempC.CopyTo(tabytTempa, ti32Tempa + ti32TempB)
tabytTempa = tobjOBEX_HEADERS.fnCreatePutHeader(tabytTempa)
’将名称、时间、文件长度等基本信息先发出去
Try
tobjIrDAClient.GetStream.Write(tabytTempa, 0, tabytTempa.Length)
Catch ex As Exception
Return False
End Try
Try
tobjIrDAClient.GetStream.Read(tabytReceiveBuffer, 0, tabytReceiveBuffer.Length)
Catch ex As Exception
’接收服务器端响应时失败
tobjIrDAClient.GetStream.Close()
tobjIrDAClient.Close()
Return False
End Try
If tabytReceiveBuffer(0)  cOBEX_SUCCESS And tabytReceiveBuffer(0)  cOBEX_CONTINUE Then
’没有收到服务器的对应的响应信息  
tobjIrDAClient.GetStream.Close()
tobjIrDAClient.Close()
Return False
End If
’开始正式发送文件的数据
Try
tobjFileStream = IO.File.Open(ni_strFilePath, IO.FileMode.Open, IO.FileACCESS.Read)
tobjBinaryReader = New IO.BinaryReader(tobjFileStream)
Catch ex As Exception
MessageBox.Show("打开文件时出现错误")
tobjIrDAClient.GetStream.Close()
tobjIrDAClient.Close()
Return False
End Try