我正在尝试通过 P/Invoke 将数据写入串行端口(明确不使用 SerialPort 类)。这是我到目前为止所拥有的:
[DllImport("kernel32", SetLastError = true)]
static extern IntPtr CreateFile(string filename, // file name
uint desiredAccess, // read? write?
uint shareMode, // sharing
uint attributes, // SecurityAttributes pointer
uint creationDisposition,
uint flagsAndAttributes,
uint templateFile);
[DllImport("kernel32", SetLastError = true)]
static extern bool WriteFile(IntPtr hFile, // handle to file
byte[] lpBuffer, // data buffer
uint nBytesToWrite, // number of bytes to write
out uint nBytesWritten, // number of bytes written
[In] ref NativeOverlapped overlapped); // overlapped buffer
const uint OPEN_EXISTING = 3;
_portHandle = CreateFile("COM1", GENERIC_READ | GENERIC_WRITE, 0, 0, OPEN_EXISTING, 0, 0);
uint bytesWritten;
var buffer = Encoding.ASCII.GetBytes("foo\r");
var overlapped = new NativeOverlapped();
WriteFile(_portHandle, buffer, (uint)buffer.Length, out bytesWritten, ref overlapped);
我得到一个 _portHandle != -1 并且可以调用 WriteFile。但是在调用之后,它什么也没做。我可以在 VS 调试模式下永远等待并等待调用返回。此外,不会抛出异常。
有任何 kernel32.dll-masters 可以帮助我吗?