提供 .Net 下调用非托管Dll内部函数的快捷方法

提供 .Net 下调用非托管Dll内部函数 的快捷方法2008年12月12日 星期五 下午 10:241，用C#实现一个DllImported 类，内部利用DllImport 访问kernel32.dll的LoadLibrary和GetProcAddress

[DllImport("kernel32.dll", EntryPoint = "LoadLibrary")]

public static extern int LoadLibrary( string lpLibFileName );

[DllImport("kernel32.dll", EntryPoint = "GetProcAddress")]

public static extern IntPtr GetProcAddress(int hModule, string lpProcName);

2，利用Marshal.GetDelegateForFunctionPointer 将非托管指针转化为委托

类代码如下：

using System;

using System.Collections.Generic;

using System.Text;

///////////////添加命名空间/////////////////////////

using System.Runtime.InteropServices;

namespace DllImported

{

public class CDllImported

{

[DllImport("kernel32.dll", EntryPoint = "LoadLibrary")]

public static extern int LoadLibrary( string lpLibFileName );

[DllImport("kernel32.dll", EntryPoint = "GetProcAddress")]

public static extern IntPtr GetProcAddress(int hModule, string lpProcName);

public CDllImported()

{

}

/// <summary>

/// 获取非托管DLL内部函数

/// </summary>

/// <param name="delegateName">托管函数定义类型，用typeof（your delegate typeof）传入 </param>

/// <param name="dllName">Dll路径 </param>

/// <param name="procName">要获取的函数名称</param>

/// <returns></returns>

public object GetApi (Type delegateName, string dllName,string procName)

{

IntPtr api = GetProcAddress(LoadLibrary(dllName), procName);

return (object)Marshal.GetDelegateForFunctionPointer(api, delegateName);

}

}

}

编译产生一个DllImported的 dll组件。

在Vb里调用Api

1 先添加上面的组件

2 定义委托 Delegate Function msgDelegate(ByVal hwnd As IntPtr, ByVal strText As String, ByVal strCaption As String, ByVal type As Int32) As Int

3 实现调用

Dim api As New DllImported.CDllImported

Dim msg As msgDelegate= api.GetApi(Gettype（msgDelegate） , "user32.dll", "MessageBoxW")

msg(IntPtr.Zero, "Done", "Change", 0)

类似的可以在C#内调用，由于类代码是C#写的，调用起来很容易，此略去。