Python 2.7.8,Windows 7,Phyton USB程序员的DLL
我对应该是大内存阵列的Data元素感到困惑,我尝试使用几种不同的定义,但是我无法理解错误试图告诉我什么。我遇到的大多数错误都是类型错误,下面的代码是我最近的错误,似乎正在调用该函数,但由于该错误而无法处理。
C API:
typedef struct tagACI_Memory_Params
{
UINT Size; // (in) Size of structure, in bytes
UINT BufferNumber; // (in) Number of buffer of interest, the first buffer number is 0
UINT LayerNumber; // (in) Number of layer of interest, the first layer number is 0
DWORD AddressLow; // (in) Low 32 bits of address, in layer units (natural to device address)
DWORD AddressHigh; // (in) High 32 bits of address, in layer units (natural to device address)
PVOID Data; // (in || out) Pointer to data to read to or write from
DWORD DataSize; // (in) Size of data to read or write, in layer units, max. 16 MB (0x1000000)
DWORD FillValue; // (in) Value to fill buffer with, used by ACI_FillLayer() only
} ACI_Memory_Params;
我的python代码:
MaxMemorySize = 1024
MemoryBuffer = ctypes.c_ubyte * MaxMemorySize
class Memory_Params(ctypes.Structure):
_fields_ = [("Size", ctypes.wintypes.UINT),
("BufferNumber", ctypes.wintypes.UINT),
("LayerNumber", ctypes.wintypes.UINT),
("AddressLow", ctypes.wintypes.DWORD),
("AddressHigh", ctypes.wintypes.DWORD),
("Data", MemoryBuffer ),
("DataSize", ctypes.wintypes.DWORD),
("FillValue", ctypes.wintypes.DWORD)
]
WriteLayer = ctypes.windll.ACI.ACI_WriteLayer
WriteLayer.argtypes = [ctypes.POINTER(Memory_Params)]
WriteLayer.restype = ctypes.HRESULT
WData = Memory_Params(ctypes.sizeof(Memory_Params),0,0,0,0,ctypes.POINTER(MemoryBuffer),15,0)
for i in range(10):
WData.Data[i] = i
print 'write result', WriteLayer(ctypes.byref(WData))
API调用返回1,表示:define ACI_ERR_INVALID_PARAMS_SIZE 1//ACI函数中的无效结构大小
更新:
我错过的关键事项:定义对象后创建和使用MemoryBuffer对象,以及如何正确定义指针。
如果其他任何人也有类似情况,请使用以下代码:
MaxMemorySize = 1024
MemoryBuffer = ctypes.c_ubyte * MaxMemorySize
class Memory_Params(ctypes.Structure):
_fields_ = [("Size", ctypes.wintypes.UINT),
("BufferNumber", ctypes.wintypes.UINT),
("LayerNumber", ctypes.wintypes.UINT),
("AddressLow", ctypes.wintypes.DWORD),
("AddressHigh", ctypes.wintypes.DWORD),
("Data", ctypes.POINTER(ctypes.c_ubyte) ),
("DataSize", ctypes.wintypes.DWORD),
("FillValue", ctypes.wintypes.DWORD)
]
WriteLayer = ctypes.windll.ACI.ACI_WriteLayer
WriteLayer.argtypes = [ctypes.POINTER(Memory_Params)]
WriteLayer.restype = ctypes.wintypes.UINT
PData = MemoryBuffer()
WData = Memory_Params(ctypes.sizeof(Memory_Params),0,0,0,0,PData,for i in range(10):
PData[i] = i
WriteLayer(ctypes.byref(WData))
最佳答案
若要更正此问题,将您的Memory_Params.Data成员的类型设置为:
ctypes.POINTER(ctypes.c_ubyte)
关于python - Python ctypes无法在结构中传递内存数组,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/29972991/