/// <summary>
/// Retrieves a structure with information about a device's capabilities.
/// </summary>
///
/// <param name="hidHandle"> a handle to a device. </param>
///
/// <returns>
/// An HIDP_CAPS structure.
/// </returns>
public static HIDP_CAPS GetDeviceCapabilities(SafeFileHandle hidHandle)
{
HIDP_CAPS Capabilities = new HID.HIDP_CAPS();
IntPtr preparsedData = new System.IntPtr();
Int32 result = 0;
Boolean success = false;
try
{
// ***
// API function: HidD_GetPreparsedData
// Purpose: retrieves a pointer to a buffer containing information about the device's capabilities.
// HidP_GetCaps and other API functions require a pointer to the buffer.
// Requires:
// A handle returned by CreateFile.
// A pointer to a buffer.
// Returns:
// True on success, False on failure.
// ***
success = HidD_GetPreparsedData(hidHandle, ref preparsedData);
// ***
// API function: HidP_GetCaps
// Purpose: find out a device's capabilities.
// For standard devices such as joysticks, you can find out the specific
// capabilities of the device.
// For a custom device where the software knows what the device is capable of,
// this call may be unneeded.
// Accepts:
// A pointer returned by HidD_GetPreparsedData
// A pointer to a HIDP_CAPS structure.
// Returns: True on success, False on failure.
// ***
result = HidP_GetCaps(preparsedData, ref Capabilities);
if ((result != 0))
{
// ***
// API function: HidP_GetValueCaps
// Purpose: retrieves a buffer containing an array of HidP_ValueCaps structures.
// Each structure defines the capabilities of one value.
// This application doesn't use this data.
// Accepts:
// A report type enumerator from hidpi.h,
// A pointer to a buffer for the returned array,
// The NumberInputValueCaps member of the device's HidP_Caps structure,
// A pointer to the PreparsedData structure returned by HidD_GetPreparsedData.
// Returns: True on success, False on failure.
// ***
Int32 vcSize = Capabilities.NumberInputValueCaps;
Byte[] valueCaps = new Byte[vcSize];
result = HidP_GetValueCaps(HidP_Input, valueCaps, ref vcSize, preparsedData);
// (To use this data, copy the ValueCaps byte array into an array of structures.)
}
}
catch (Exception)
{
throw;
}
finally
{
// ***
// API function: HidD_FreePreparsedData
// Purpose: frees the buffer reserved by HidD_GetPreparsedData.
// Accepts: A pointer to the PreparsedData structure returned by HidD_GetPreparsedData.
// Returns: True on success, False on failure.
// ***
if (preparsedData != IntPtr.Zero)
{
success = HidD_FreePreparsedData(preparsedData);
}
}
return Capabilities;
}
/// <summary>
/// Retrieves a structure with information about a device's capabilities.
/// </summary>
///
/// <param name="hidHandle"> a handle to a device. </param>
///
/// <returns>
/// An HIDP_CAPS structure.
/// </returns>
public static HIDP_CAPS GetDeviceCapabilities(SafeFileHandle hidHandle)
{
HIDP_CAPS Capabilities = new HID.HIDP_CAPS();
IntPtr preparsedData = new System.IntPtr();
Int32 result = 0;
Boolean success = false;
try
{
// ***
// API function: HidD_GetPreparsedData
// Purpose: retrieves a pointer to a buffer containing information about the device's capabilities.
// HidP_GetCaps and other API functions require a pointer to the buffer.
// Requires:
// A handle returned by CreateFile.
// A pointer to a buffer.
// Returns:
// True on success, False on failure.
// ***
success = HidD_GetPreparsedData(hidHandle, ref preparsedData);
// ***
// API function: HidP_GetCaps
// Purpose: find out a device's capabilities.
// For standard devices such as joysticks, you can find out the specific
// capabilities of the device.
// For a custom device where the software knows what the device is capable of,
// this call may be unneeded.
// Accepts:
// A pointer returned by HidD_GetPreparsedData
// A pointer to a HIDP_CAPS structure.
// Returns: True on success, False on failure.
// ***
result = HidP_GetCaps(preparsedData, ref Capabilities);
if ((result != 0))
{
// ***
// API function: HidP_GetValueCaps
// Purpose: retrieves a buffer containing an array of HidP_ValueCaps structures.
// Each structure defines the capabilities of one value.
// This application doesn't use this data.
// Accepts:
// A report type enumerator from hidpi.h,
// A pointer to a buffer for the returned array,
// The NumberInputValueCaps member of the device's HidP_Caps structure,
// A pointer to the PreparsedData structure returned by HidD_GetPreparsedData.
// Returns: True on success, False on failure.
// ***
Int32 vcSize = Capabilities.NumberInputValueCaps;
Byte[] valueCaps = new Byte[vcSize];
result = HidP_GetValueCaps(HidP_Input, valueCaps, ref vcSize, preparsedData);
// (To use this data, copy the ValueCaps byte array into an array of structures.)
}
}
catch (Exception)
{
throw;
}
finally
{
// ***
// API function: HidD_FreePreparsedData
// Purpose: frees the buffer reserved by HidD_GetPreparsedData.
// Accepts: A pointer to the PreparsedData structure returned by HidD_GetPreparsedData.
// Returns: True on success, False on failure.
// ***
if (preparsedData != IntPtr.Zero)
{
success = HidD_FreePreparsedData(preparsedData);
}
}
return(Capabilities);
}
