ReadFile函数参数意义,该怎么解决

ReadFile函数参数意义
请问ReadFile(hCom,   lpStr^,   dwLength,   dwLength,   nil)函数中各参数的意义

[解决办法]
BOOL ReadFile(
HANDLE hFile, // handle to file
LPVOID lpBuffer, // data buffer
DWORD nNumberOfBytesToRead, // number of bytes to read
LPDWORD lpNumberOfBytesRead, // number of bytes read
LPOVERLAPPED lpOverlapped // overlapped buffer
);