public void OpenDevice(String DevicePath)
{
uint ErrorStatusWrite;
uint ErrorStatusRead;
// Close device first
CloseDevice();
// Open WriteHandle
WriteHandleToUSBDevice = CreateFile(DevicePath, GENERIC_WRITE, FILE_SHARE_READ | FILE_SHARE_WRITE, IntPtr.Zero, OPEN_EXISTING, 0, IntPtr.Zero);
ErrorStatusWrite = (uint)Marshal.GetLastWin32Error();
// Open ReadHandle
ReadHandleToUSBDevice = CreateFile(DevicePath, GENERIC_READ, FILE_SHARE_READ | FILE_SHARE_WRITE, IntPtr.Zero, OPEN_EXISTING, 0, IntPtr.Zero);
ErrorStatusRead = (uint)Marshal.GetLastWin32Error();
// Check if both handles were opened successfully
if ((ErrorStatusWrite == ERROR_SUCCESS) && (ErrorStatusRead == ERROR_SUCCESS))
{
ConnectionStatus = UsbConnectionStatus.Connected;
}
else // For some reason the device was physically plugged in, but one or both of the read/write handles didn't open successfully
{
ConnectionStatus = UsbConnectionStatus.NotWorking;
if (ErrorStatusWrite == ERROR_SUCCESS)
{
WriteHandleToUSBDevice.Close();
}
if (ErrorStatusRead == ERROR_SUCCESS)
{
ReadHandleToUSBDevice.Close();
}
}
// Raise event if there are any subscribers
if (RaiseConnectionStatusChangedEvent != null)
{
RaiseConnectionStatusChangedEvent(this, new ConnectionStatusEventArgs(ConnectionStatus));
}
// Start async thread if connection has been established
if (ConnectionStatus == UsbConnectionStatus.Connected)
{
//UsbThread.RunWorkerAsync();
}
}
// Close connection to the USB device
public void CloseDevice()
{
// Save current status
UsbConnectionStatus previousStatus = ConnectionStatus;
// Close write and read handles if a device is connected
if (ConnectionStatus==UsbConnectionStatus.Connected)
{
WriteHandleToUSBDevice.Close();
ReadHandleToUSBDevice.Close();
}
// Set status to disconnected
ConnectionStatus = UsbConnectionStatus.Disconnected;
// Stop async thread if connection has been established
//UsbThread.CancelAsync();
// Raise event if the status has changed and if there are any subscribers
if (ConnectionStatus!=previousStatus)
{
if (RaiseConnectionStatusChangedEvent != null)
{
RaiseConnectionStatusChangedEvent(this, new ConnectionStatusEventArgs(ConnectionStatus));
}
}
}
public ConnectionStatusEventArgs(UsbConnectionStatus status)
{
this.ConnectionStatus = status;
}
