<p>Any ideas how i can best drive a USB POS printer from c#.
POS printers are usually serial, TCP/IP or USB based.
I know how to accomplish serial and TCP/IP but have no idea about communications through USB in C#.
I know that there is a layer available from Microsoft called POS.NET, but I want to try and avoid using this.
Any ideas or any C# libraries that people can recomend would be really appreciated.  Thanks</p>

If the printer registers itself as a Human Interface Device, you can
P/INVOKE into the appropriate Win32 APIs
. Here are the signatures:
```
```
[ DllImport( "hid.dll", SetLastError=true ) ]
    public static extern Boolean 
    HidD_FlushQueue( SafeFileHandle HidDeviceObject );        

    [ DllImport( "hid.dll", SetLastError=true ) ]
    public static extern Boolean 
    HidD_FreePreparsedData( ref IntPtr PreparsedData );        

    [ DllImport( "hid.dll", SetLastError=true ) ]
    public static extern Boolean 
    HidD_GetAttributes(  SafeFileHandle HidDeviceObject
                       , ref HIDD_ATTRIBUTES Attributes );        

    [ DllImport( "hid.dll", SetLastError=true ) ]
    public static extern Boolean 
    HidD_GetFeature(  SafeFileHandle HidDeviceObject
                    , ref Byte lpReportBuffer
                    , Int32 ReportBufferLength );        

    [ DllImport( "hid.dll", SetLastError=true ) ]
    public static extern Boolean 
    HidD_GetInputReport( SafeFileHandle HidDeviceObject
                        ,ref Byte lpReportBuffer
                        ,Int32 ReportBufferLength );        

    [ DllImport( "hid.dll", SetLastError=true ) ]
    public static extern void HidD_GetHidGuid( ref System.Guid HidGuid );

    [ DllImport( "hid.dll", SetLastError=true ) ]
    public static extern Boolean 
    HidD_GetNumInputBuffers(  SafeFileHandle HidDeviceObject
                            , ref Int32 NumberBuffers );        

    [ DllImport( "hid.dll", SetLastError=true ) ]
    public static extern Boolean 
    HidD_GetPreparsedData( SafeFileHandle HidDeviceObject
                          ,ref IntPtr PreparsedData );

    [ DllImport( "hid.dll", SetLastError=true ) ]
    public static extern Boolean 
    HidD_SetFeature(  SafeFileHandle HidDeviceObject
                    , ref Byte lpReportBuffer
                    , Int32 ReportBufferLength );

    [ DllImport( "hid.dll", SetLastError=true ) ]
    public static extern Boolean 
    HidD_SetNumInputBuffers( SafeFileHandle HidDeviceObject
                            ,Int32 NumberBuffers );

    [ DllImport( "hid.dll", SetLastError=true ) ]
    public static extern Boolean 
    HidD_SetOutputReport( SafeFileHandle HidDeviceObject
                         ,ref Byte lpReportBuffer
                         ,Int32 ReportBufferLength );

    [ DllImport( "hid.dll", SetLastError=true ) ]
    public static extern Int32 
    HidP_GetCaps( IntPtr PreparsedData, ref HIDP_CAPS Capabilities );

    [ DllImport( "hid.dll", SetLastError=true ) ]
    public static extern Int32 
    HidP_GetValueCaps(  Int16 ReportType
                      , ref Byte ValueCaps
                      , ref Int16 ValueCapsLength
                      , IntPtr PreparsedData );
```
```