用 LoadLibraryExW 函数测试加载 dll （CSharp、Windows）

效果如下：

$ llbtest "E:Developeremgucv-windesktop 3.3.0.2824libsx64"
LoadLibraryExW PATH: E:Developeremgucv-windesktop 3.3.0.2824libsx64
E:Developeremgucv-windesktop 3.3.0.2824libsx64concrt140.dll......[OK] 140734063771648......Free: [OK]
E:Developeremgucv-windesktop 3.3.0.2824libsx64cvextern.dll......[OK] 140733428531200......Free: [OK]
E:Developeremgucv-windesktop 3.3.0.2824libsx64msvcp140.dll......[OK] 140734063509504......Free: [OK]
E:Developeremgucv-windesktop 3.3.0.2824libsx64opencv_ffmpeg330_64.dll......[OK] 1724645376......Free: [OK]
E:Developeremgucv-windesktop 3.3.0.2824libsx64vcruntime140.dll......[OK] 140734064033792......Free: [OK]
-- Completed --

llbtest.cs 源代码：

用csc llbtest.cs编译即可

using System;
using System.ComponentModel;
using System.IO;
using System.Runtime.InteropServices;

class Program
{
    static void Main(string[] args)
    {
        if (args.Length == 0 || args.Length > 2)
        {
            ShowHelp();
            return;
        }
        var path = args[0];
        if (!Directory.Exists(path))
        {
            ShowHelp();
            return;
        }

        var files = Directory.EnumerateFiles(path, "*.dll");
        Console.WriteLine($"LoadLibraryExW PATH: {path}");
        foreach (var file in files)
        {
            Console.Write(file);
            const int loadLibrarySearchDllLoadDir = 0x00000100;
            const int loadLibrarySearchDefaultDirs = 0x00001000;
            //const int loadLibrarySearchUserDirs = 0x00000400;
            IntPtr handler = NativeMethods.LoadLibraryExW(file, IntPtr.Zero, loadLibrarySearchDllLoadDir | loadLibrarySearchDefaultDirs);
            //IntPtr handler = LoadLibraryEx(dllname, IntPtr.Zero, loadLibrarySearchUserDirs);
            if (handler == IntPtr.Zero)
            {
                var error = Marshal.GetLastWin32Error();
                var ex = new Win32Exception(error);
                Console.WriteLine($"......[ERROR] {ex.NativeErrorCode}: {ex.Message}");
            }
            else
            {
                Console.Write($"......[OK] {handler}");
                var freeLibrary = NativeMethods.FreeLibrary(handler);
                Console.WriteLine($"......Free: {(freeLibrary ? "[OK]" : "[ERROR]")}");
            }
        }
        Console.WriteLine("-- Completed --");
        if(args.Length == 2 && args[1] == "...")
        {
            Console.Write("Press any key to exit...");
            Console.ReadKey(true);
            Console.WriteLine();
        }
    }

    private static void ShowHelp()
    {
        var x = AppDomain.CurrentDomain.FriendlyName;
        Console.WriteLine($"Usage:
	{x} <path> [...]
	path	The directory path that includes *.dll files
	...	Pause me when completed.");
    }
}





[StructLayout(System.Runtime.InteropServices.LayoutKind.Sequential)]
public struct HINSTANCE__
{

    /// int
    public int unused;
}

public partial class NativeMethods
{

    /// Return Type: HMODULE->HINSTANCE->HINSTANCE__*
    ///lpLibFileName: LPCWSTR->WCHAR*
    ///hFile: HANDLE->void*
    ///dwFlags: DWORD->unsigned int
    [DllImport("kernel32.dll", EntryPoint = "LoadLibraryExW", SetLastError = true)]
    public static extern System.IntPtr LoadLibraryExW([In()] [MarshalAs(System.Runtime.InteropServices.UnmanagedType.LPWStr)] string lpLibFileName, System.IntPtr hFile, uint dwFlags);


    /// Return Type: BOOL->int
    ///hLibModule: HMODULE->HINSTANCE->HINSTANCE__*
    [DllImport("kernel32.dll", EntryPoint = "FreeLibrary")]
    [return: MarshalAs(System.Runtime.InteropServices.UnmanagedType.Bool)]
    public static extern bool FreeLibrary([In()] System.IntPtr hLibModule);
}