c# - 如何动态加载和卸载原生 DLL 文件？

Question

我有一个有问题的第三方 DLL 文件，在执行一段时间后，它开始抛出访问冲突异常。发生这种情况时，我想重新加载该 DLL 文件。我该怎么做？

Answer 1

试试这个

[DllImport("kernel32.dll", CharSet = CharSet.Auto, SetLastError = true)]
private static extern IntPtr LoadLibrary(string libname);

[DllImport("kernel32.dll", CharSet = CharSet.Auto)]
private static extern bool FreeLibrary(IntPtr hModule);

//Load
IntPtr Handle = LoadLibrary(fileName);
if (Handle == IntPtr.Zero)
{
     int errorCode = Marshal.GetLastWin32Error();
     throw new Exception(string.Format("Failed to load library (ErrorCode: {0})",errorCode));
}

//Free
if(Handle != IntPtr.Zero)
        FreeLibrary(Handle);

如果您想先调用函数，您必须创建与此函数匹配的委托(delegate)，然后使用 WinApi GetProcAddress

[DllImport("kernel32.dll", CharSet = CharSet.Ansi)]
private static extern IntPtr GetProcAddress(IntPtr hModule, string lpProcName); 


IntPtr funcaddr = GetProcAddress(Handle,functionName);
YourFunctionDelegate function = Marshal.GetDelegateForFunctionPointer(funcaddr,typeof(YourFunctionDelegate )) as YourFunctionDelegate ;
function.Invoke(pass here your parameters);