我正在使用[DLLImport]
属性来访问我的.NET代码中的一堆C++函数。
现在,我通过以下方式拥有所有功能:
const string DLL_Path = "path\\to\\my\\dll.dll";
[DllImport(DLL_Path,
CallingConvention = CallingConvention.StdCall,
CharSet = CharSet.Ansi)]
public static extern int MyFunction1();
[DllImport(DLL_Path,
CallingConvention = CallingConvention.StdCall,
CharSet = CharSet.Ansi)]
public static extern ErrorCode MyFunction2(int id);
[DllImport(DLL_Path,
CallingConvention = CallingConvention.StdCall,
CharSet = CharSet.Ansi)]
public static extern ErrorCode MyFunction3(string server, byte timeout,
ref int connection_id, ref DeviceInfo pInfos);
[DllImport(DLL_Path,
CallingConvention = CallingConvention.StdCall,
CharSet = CharSet.Ansi)]
public static extern ErrorCode MyFunction4([MarshalAs(UnmanagedType.LPArray)] byte[] pVersion,
ref int psize);
[DllImport(DLL_Path,
CallingConvention = CallingConvention.StdCall,
CharSet = CharSet.Ansi)]
public static extern ErrorCode MyFunction5(int errorcode,
[MarshalAs(UnmanagedType.LPTStr)] string pmsg, ref int psize);
这真是让人不悦:重复属性似乎效率低下,并且破坏了函数原型(prototype)的可读性。特别是因为我要导入20或30个函数。
我想知道我是否只能在某个地方有一个
[DllImport(DLL_Path, CallingConvention = CallingConvention.StdCall, CharSet = CharSet.Ansi)]
部分,并且可以更清楚地识别出函数定义,例如以下伪代码:const string DLL_Path = "path\\to\\my\\dll.dll";
// some code defining a section which tells that the next functions are DLLImport
[DllImport(DLL_Path, CallingConvention = CallingConvention.StdCall, CharSet = CharSet.Ansi)]
{
public static extern int MyFunction1();
public static extern ErrorCode MyFunction2(int id);
public static extern ErrorCode MyFunction3(string server, byte timeout, ref int connection_id, ref DeviceInfo pInfos);
public static extern ErrorCode MyFunction4([MarshalAs(UnmanagedType.LPArray)] byte[] pVersion, ref int psize);
public static extern ErrorCode MyFunction5(int errorcode, [MarshalAs(UnmanagedType.LPTStr)] string pmsg, ref int psize);
}
这可能吗?
我在SO中找到了这个问题:Shorten amount of DllImport in C#?,但它建议通过
LoadLibrary
和GetProcAddress
动态加载函数,但我觉得可读性较差。 最佳答案
不,没有办法将Attributes简化为一个声明。您需要将Attribute应用于所有方法。
但是您至少可以将Attribute声明缩短为[DllImport(DLL_Path)]
,因为您为 CallingConvention
和 CharSet
指定的值与默认值相同。
关于C#:一个用于多个声明的属性(DLLImport),我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/15781627/