Replace DllImport & flags with CSWin32

Flow.Launcher/Flow.Launcher.csproj

@@ -90,6 +90,10 @@
     </PackageReference>
     <PackageReference Include="InputSimulator" Version="1.0.4" />
     <PackageReference Include="Microsoft.Toolkit.Uwp.Notifications" Version="7.1.3" />
+    <PackageReference Include="Microsoft.Windows.CsWin32" Version="0.3.106">
+      <PrivateAssets>all</PrivateAssets>
+      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
+    </PackageReference>
     <!-- ModernWpfUI v0.9.5 introduced WinRT changes that causes Notification platform unavailable error on some machines -->
     <!-- https://github.com/Flow-Launcher/Flow.Launcher/issues/1772#issuecomment-1502440801 -->
     <PackageReference Include="ModernWpfUI" Version="0.9.4" />

Flow.Launcher/Helper/DWMDropShadow.cs

@@ -1,20 +1,15 @@
 using System;
-using System.Drawing.Printing;
-using System.Runtime.InteropServices;
 using System.Windows;
 using System.Windows.Interop;
+using Windows.Win32;
+using Windows.Win32.Graphics.Dwm;
+using Windows.Win32.UI.Controls;
 
 namespace Flow.Launcher.Helper;
 
 public class DwmDropShadow
 {
 
-    [DllImport("dwmapi.dll", PreserveSig = true)]
-    private static extern int DwmSetWindowAttribute(IntPtr hwnd, int attr, ref int attrValue, int attrSize);
-
-    [DllImport("dwmapi.dll")]
-    private static extern int DwmExtendFrameIntoClientArea(IntPtr hWnd, ref Margins pMarInset);
-
     /// <summary>
     /// Drops a standard shadow to a WPF Window, even if the window isborderless. Only works with DWM (Vista and Seven).
     /// This method is much more efficient than setting AllowsTransparency to true and using the DropShadow effect,
@@ -43,18 +38,18 @@ public class DwmDropShadow
     /// </summary>
     /// <param name="window">Window to which the shadow will be applied</param>
     /// <returns>True if the method succeeded, false if not</returns>
-    private static bool DropShadow(Window window)
+    private unsafe static bool DropShadow(Window window)
     {
         try
         {
             WindowInteropHelper helper = new WindowInteropHelper(window);
             int val = 2;
-            int ret1 = DwmSetWindowAttribute(helper.Handle, 2, ref val, 4);
+            int ret1 = PInvoke.DwmSetWindowAttribute(new(helper.Handle), DWMWINDOWATTRIBUTE.DWMWA_NCRENDERING_POLICY, &val, 4);
 
             if (ret1 == 0)
             {
-                Margins m = new Margins { Bottom = 0, Left = 0, Right = 0, Top = 0 };
-                int ret2 = DwmExtendFrameIntoClientArea(helper.Handle, ref m);
+                var m = new MARGINS { cyBottomHeight = 0, cxLeftWidth = 0, cxRightWidth = 0, cyTopHeight = 0 };
+                int ret2 = PInvoke.DwmExtendFrameIntoClientArea(new(helper.Handle), &m);
                 return ret2 == 0;
             }
             else

Flow.Launcher/Helper/WallpaperPathRetrieval.cs

@@ -1,24 +1,21 @@
-using System;
-using System.Linq;
-using System.Runtime.InteropServices;
+using System.Linq;
 using System.Text;
 using System.Windows.Media;
 using Microsoft.Win32;
+using Windows.Win32;
+using Windows.Win32.UI.WindowsAndMessaging;
 
 namespace Flow.Launcher.Helper;
 
 public static class WallpaperPathRetrieval
 {
-    [DllImport("user32.dll", CharSet = CharSet.Unicode)]
-    private static extern Int32 SystemParametersInfo(UInt32 action,
-        Int32 uParam, StringBuilder vParam, UInt32 winIni);
-    private static readonly UInt32 SPI_GETDESKWALLPAPER = 0x73;
-    private static int MAX_PATH = 260;
+    
+    private static readonly int MAX_PATH = 260;
 
-    public static string GetWallpaperPath()
+    public static unsafe string GetWallpaperPath()
     {
         var wallpaper = new StringBuilder(MAX_PATH);
-        SystemParametersInfo(SPI_GETDESKWALLPAPER, MAX_PATH, wallpaper, 0);
+        PInvoke.SystemParametersInfo(SYSTEM_PARAMETERS_INFO_ACTION.SPI_GETDESKWALLPAPER, (uint)MAX_PATH, &wallpaper, 0);
 
         var str = wallpaper.ToString();
         if (string.IsNullOrEmpty(str))

Flow.Launcher/Helper/WindowsInteropHelper.cs

@@ -1,75 +1,50 @@
 using System;
 using System.Drawing;
-using System.Runtime.InteropServices;
-using System.Text;
 using System.Windows;
 using System.Windows.Forms;
 using System.Windows.Interop;
 using System.Windows.Media;
+using Windows.Win32;
+using Windows.Win32.Foundation;
+using Windows.Win32.UI.WindowsAndMessaging;
 using Point = System.Windows.Point;
 
 namespace Flow.Launcher.Helper;
 
 public class WindowsInteropHelper
 {
-    private const int GWL_STYLE = -16; //WPF's Message code for Title Bar's Style
-    private const int WS_SYSMENU = 0x80000; //WPF's Message code for System Menu
-    private static IntPtr _hwnd_shell;
-    private static IntPtr _hwnd_desktop;
+    private static HWND _hwnd_shell;
+    private static HWND _hwnd_desktop;
 
     //Accessors for shell and desktop handlers
     //Will set the variables once and then will return them
-    private static IntPtr HWND_SHELL
+    private static HWND HWND_SHELL
     {
         get
         {
-            return _hwnd_shell != IntPtr.Zero ? _hwnd_shell : _hwnd_shell = GetShellWindow();
+            return _hwnd_shell != HWND.Null ? _hwnd_shell : _hwnd_shell = PInvoke.GetShellWindow();
         }
     }
-    private static IntPtr HWND_DESKTOP
+
+    private static HWND HWND_DESKTOP
     {
         get
         {
-            return _hwnd_desktop != IntPtr.Zero ? _hwnd_desktop : _hwnd_desktop = GetDesktopWindow();
+            return _hwnd_desktop != HWND.Null ? _hwnd_desktop : _hwnd_desktop = PInvoke.GetDesktopWindow();
         }
     }
 
-    [DllImport("user32.dll", SetLastError = true)]
-    internal static extern int GetWindowLong(IntPtr hWnd, int nIndex);
-
-    [DllImport("user32.dll")]
-    internal static extern int SetWindowLong(IntPtr hWnd, int nIndex, int dwNewLong);
-
-    [DllImport("user32.dll")]
-    internal static extern IntPtr GetForegroundWindow();
-
-    [DllImport("user32.dll")]
-    internal static extern IntPtr GetDesktopWindow();
-
-    [DllImport("user32.dll")]
-    internal static extern IntPtr GetShellWindow();
-
-    [DllImport("user32.dll", SetLastError = true)]
-    internal static extern int GetWindowRect(IntPtr hwnd, out RECT rc);
-
-    [DllImport("user32.dll", SetLastError = true, CharSet = CharSet.Auto)]
-    internal static extern int GetClassName(IntPtr hWnd, StringBuilder lpClassName, int nMaxCount);
-
-    [DllImport("user32.DLL")]
-    public static extern IntPtr FindWindowEx(IntPtr hwndParent, IntPtr hwndChildAfter, string lpszClass, string lpszWindow);
-
-
     const string WINDOW_CLASS_CONSOLE = "ConsoleWindowClass";
     const string WINDOW_CLASS_WINTAB = "Flip3D";
     const string WINDOW_CLASS_PROGMAN = "Progman";
     const string WINDOW_CLASS_WORKERW = "WorkerW";
 
-    public static bool IsWindowFullscreen()
+    public unsafe static bool IsWindowFullscreen()
     {
         //get current active window
-        IntPtr hWnd = GetForegroundWindow();
+        var hWnd = PInvoke.GetForegroundWindow();
 
-        if (hWnd.Equals(IntPtr.Zero))
+        if (hWnd.Equals(HWND.Null))
         {
             return false;
         }
@@ -80,9 +55,16 @@ public class WindowsInteropHelper
             return false;
         }
 
-        StringBuilder sb = new StringBuilder(256);
-        GetClassName(hWnd, sb, sb.Capacity);
-        string windowClass = sb.ToString();
+        string windowClass;
+        int capacity = 256;
+        char[] buffer = new char[capacity];
+        fixed (char* pBuffer = buffer)
+        {
+            PInvoke.GetClassName(hWnd, pBuffer, capacity);
+            int validLength = Array.IndexOf(buffer, '\0');
+            if (validLength < 0) validLength = capacity;
+            windowClass = new string(buffer, 0, validLength);
+        }
 
         //for Win+Tab (Flip3D)
         if (windowClass == WINDOW_CLASS_WINTAB)
@@ -90,20 +72,19 @@ public class WindowsInteropHelper
             return false;
         }
 
-        RECT appBounds;
-        GetWindowRect(hWnd, out appBounds);
+        PInvoke.GetWindowRect(hWnd, out var appBounds);
 
         //for console (ConsoleWindowClass), we have to check for negative dimensions
         if (windowClass == WINDOW_CLASS_CONSOLE)
         {
-            return appBounds.Top < 0 && appBounds.Bottom < 0;
+            return appBounds.top < 0 && appBounds.bottom < 0;
         }
 
         //for desktop (Progman or WorkerW, depends on the system), we have to check
         if (windowClass is WINDOW_CLASS_PROGMAN or WINDOW_CLASS_WORKERW)
         {
-            IntPtr hWndDesktop = FindWindowEx(hWnd, IntPtr.Zero, "SHELLDLL_DefView", null);
-            hWndDesktop = FindWindowEx(hWndDesktop, IntPtr.Zero, "SysListView32", "FolderView");
+            var hWndDesktop = PInvoke.FindWindowEx(hWnd, HWND.Null, "SHELLDLL_DefView", null);
+            hWndDesktop = PInvoke.FindWindowEx(hWndDesktop, HWND.Null, "SysListView32", "FolderView");
             if (!hWndDesktop.Equals(IntPtr.Zero))
             {
                 return false;
@@ -111,7 +92,7 @@ public class WindowsInteropHelper
         }
 
         Rectangle screenBounds = Screen.FromHandle(hWnd).Bounds;
-        return (appBounds.Bottom - appBounds.Top) == screenBounds.Height && (appBounds.Right - appBounds.Left) == screenBounds.Width;
+        return (appBounds.bottom - appBounds.top) == screenBounds.Height && (appBounds.right - appBounds.left) == screenBounds.Width;
     }
 
     /// <summary>
@@ -120,8 +101,8 @@ public class WindowsInteropHelper
     /// </summary>
     public static void DisableControlBox(Window win)
     {
-        var hwnd = new WindowInteropHelper(win).Handle;
-        SetWindowLong(hwnd, GWL_STYLE, GetWindowLong(hwnd, GWL_STYLE) & ~WS_SYSMENU);
+        var hwnd = new HWND(new WindowInteropHelper(win).Handle);
+        PInvoke.SetWindowLong(hwnd, WINDOW_LONG_PTR_INDEX.GWL_STYLE, PInvoke.GetWindowLong(hwnd, WINDOW_LONG_PTR_INDEX.GWL_STYLE) & ~(int)WINDOW_STYLE.WS_SYSMENU);
     }
 
     /// <summary>
@@ -146,14 +127,4 @@ public class WindowsInteropHelper
         }
         return new Point((int)(matrix.M11 * unitX), (int)(matrix.M22 * unitY));
     }
-
-
-    [StructLayout(LayoutKind.Sequential)]
-    public struct RECT
-    {
-        public int Left;
-        public int Top;
-        public int Right;
-        public int Bottom;
-    }
 }

Flow.Launcher/MainWindow.xaml.cs

@@ -26,7 +26,7 @@ using System.Media;
 using DataObject = System.Windows.DataObject;
 using System.Windows.Media;
 using System.Windows.Interop;
-using System.Runtime.InteropServices;
+using Windows.Win32;
 
 namespace Flow.Launcher
 {
@@ -34,9 +34,6 @@ namespace Flow.Launcher
     {
         #region Private Fields
 
-        [DllImport("user32.dll", SetLastError = true, CharSet = CharSet.Unicode)]
-        public static extern IntPtr SetForegroundWindow(IntPtr hwnd);
-
         private readonly Storyboard _progressBarStoryboard = new Storyboard();
         private bool isProgressBarStoryboardPaused;
         private Settings _settings;
@@ -424,7 +421,7 @@ namespace Flow.Launcher
                         // Get context menu handle and bring it to the foreground
                         if (PresentationSource.FromVisual(contextMenu) is HwndSource hwndSource)
                         {
-                            _ = SetForegroundWindow(hwndSource.Handle);
+                            PInvoke.SetForegroundWindow(new(hwndSource.Handle));
                         }
 
                         contextMenu.Focus();
@@ -692,7 +689,7 @@ namespace Flow.Launcher
                     screen = Screen.PrimaryScreen;
                     break;
                 case SearchWindowScreens.Focus:
-                    IntPtr foregroundWindowHandle = WindowsInteropHelper.GetForegroundWindow();
+                    var foregroundWindowHandle = PInvoke.GetForegroundWindow().Value;
                     screen = Screen.FromHandle(foregroundWindowHandle);
                     break;
                 case SearchWindowScreens.Custom:

Flow.Launcher/NativeMethods.txt

@@ -0,0 +1,14 @@
+DwmSetWindowAttribute
+DwmExtendFrameIntoClientArea
+SystemParametersInfo
+SetForegroundWindow
+
+GetWindowLong
+SetWindowLong
+GetForegroundWindow
+GetDesktopWindow
+GetShellWindow
+GetWindowRect
+GetClassName
+FindWindowEx
+WINDOW_STYLE