我在C中的结构如下

 /* this structure contains the xfoil output parameters vs angle of attack */
    typedef struct xfoil_outputdata_struct
    {
     double *pAlfa;
     double *pCL;
     double *pCM;
     double *pCDi;
     double *pCDo;
     double *pCPmax;
     long nEntries;
    } XFOIL_OUTPUT_DATA;

    /* Here are the function prototypes for XFoil */
    __declspec(dllexport) XFOIL_OUTPUT_DATA *xfoilResults(); /* get output from xfoil */

我使用XFoilResults将这个结构拉回到C#

我的DLL Imports语句如下：

 [DllImport("xfoilapi.dll")]
        public static extern void xfoilResults();

这个对吗？我无法控制C代码.我只需要能够将结构拖入C#中即可.到目前为止,我拥有的C#结构如下

[StructLayout(LayoutKind.Sequential)]
    public  struct xfoilResults
    {
     IntPtr pAlfa;
        IntPtr pCL;
        IntPtr pCM;
        IntPtr pCDi;
        IntPtr pCDo;
        IntPtr pCPmax;
     long nEntries;
    }

如何用C代码中的数据填充此C#结构？

解决方法:

StructLayout必须在类上.

这应该可以解决问题：

[DllImport("xfoilapi.dll")]
public static extern IntPtr GetXfoilResults();

[StructLayout(LayoutKind.Sequential)]
public class XfoilResults
{
    IntPtr pAlfa;
    IntPtr pCL;
    IntPtr pCM;
    IntPtr pCDi;
    IntPtr pCDo;
    IntPtr pCPmax;
    int nEntries; // thanks to guys for reminding me long is 4 bytes
}

XfoilResults xf  ==  new XfoilResults();
Marshal.PtrToStructure(GetXfoilResults(), xf);