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);

这并不令人满意：重复属性似乎效率低下并破坏了函数原型的可读性.特别是因为我有20或30个函数要导入.

我想知道我是否可以在某个地方使用[DllImport(DLL_Path,CallingConvention = CallingConvention.StdCall,CharSet = CharSet.Ansi)]部分并更清楚地识别函数定义,就像这个伪代码：

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：Shorten amount of DllImport in C#?中发现了这个问题,但它建议通过LoadLibrary和GetProcAddress动态加载函数,我发现它们的可读性较差.

解决方法:

不,没有办法将属性简化为单个声明.您需要将属性应用于所有方法.

但您至少可以将属性声明缩短为[DllImport(DLL_Path)],因为您为CallingConvention和CharSet指定的值与默认值相同.

标签：c,attributes,dllimport

来源： https://codeday.me/bug/20190629/1328035.html