急救,用API调用摄像头来拍照时遇到的问题!
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对 PInvoke 函数“getPicture!Video.VideoWork::SendMessage”的调用导致堆栈不对称。原因可能是托管的 PInvoke 签名与非托管的目标签名不匹配。请检查 PInvoke 签名的调用约定和参数与非托管的目标签名是否匹配。
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[DllImport("avicap32.dll")]
private static extern IntPtr capCreateCaptureWindowA(byte[] lpszWindowName, int dwStyle, int x, int y, int nWidth, int nHeight, IntPtr hWndParent, int nID);
[DllImport("avicap32.dll")]
private static extern int capGetVideoFormat(IntPtr hWnd, IntPtr psVideoFormat, int wSize );
[DllImport("User32.dll")]
private static extern bool SendMessage(IntPtr hWnd, int wMsg, int wParam, long lParam);
/// <summary>
/// 开始显示图像
/// </summary>
public bool Start()
{
if (bWorkStart)
return bWorkStart;
byte[] lpszName = new byte[100];
//DeviceSelector ds = new DeviceSelector(s);
hWndC = capCreateCaptureWindowA(lpszName,WS_CHILD|WS_VISIBLE ,mLeft,mTop,mWidth,mHeight,mControlPtr,0);
if (hWndC.ToInt32() != 0)
{
SendMessage(hWndC, WM_CAP_SET_CALLBACK_VIDEOSTREAM, 0, 0);
SendMessage(hWndC, WM_CAP_SET_CALLBACK_ERROR, 0, 0);
SendMessage(hWndC, WM_CAP_SET_CALLBACK_STATUSA, 0, 0);
SendMessage(hWndC, WM_CAP_DRIVER_CONNECT, 0, 0);
SendMessage(hWndC, WM_CAP_SET_SCALE, 1, 0);
SendMessage(hWndC, WM_CAP_SET_PREVIEWRATE, 66, 0);
SendMessage(hWndC, WM_CAP_SET_OVERLAY, 1, 0);
SendMessage(hWndC, WM_CAP_SET_PREVIEW, 1, 0);
bWorkStart = true;
//Global.log.Write("SendMessage");
}
return bWorkStart;
}
用的这种方法,请高手帮帮忙!