[DllImport("standerMFC.dll")]

    public static extern  int PReadUID(ref HHFC_SET stru);

[AttributeUsage(AttributeTargets.Method)]

public class DllImportAttribute: System.Attribute

{

    public DllImportAttribute(string dllName) {…} //定位参数为dllName

    public CallingConvention CallingConvention; //入口点调用约定

    public CharSet CharSet;                                   //入口点采用的字符接

    public string EntryPoint;  //入口点名称

    public bool ExactSpelling;   //是否必须与指示的入口点拼写完全一致，默认false

    public bool PreserveSig;  //方法的签名是被保留还是被转换

    public bool SetLastError;  //FindLastError方法的返回值保存在这里

    public string Value { get {…} }

}