ContextMenu (windows only)

src/GuiApp/Avalonia/FileTime.GuiApp/Helper/NativeMethodHelpers.cs

@@ -0,0 +1,71 @@
+using System.Drawing;
+using System.Runtime.InteropServices;
+using System.Text;
+
+namespace FileTime.GuiApp.Helper;
+
+public static class WindowsNativeMethods
+{
+    [DllImport("kernel32.dll", CharSet = CharSet.Unicode, SetLastError = true, BestFitMapping = false, ThrowOnUnmappableChar = true)]
+    internal static extern IntPtr LoadLibrary(string lpLibFileName);
+
+    [DllImport("user32.dll", CharSet = CharSet.Unicode, SetLastError = true, BestFitMapping = false, ThrowOnUnmappableChar = true)]
+    internal static extern int LoadString(IntPtr hInstance, uint wID, StringBuilder lpBuffer, int nBufferMax);
+
+    [DllImport("user32.dll")]
+    public static extern IntPtr LoadIcon(IntPtr hInstance, IntPtr lpIconName);
+
+    [DllImport("kernel32.dll")]
+    public static extern int FreeLibrary(IntPtr hLibModule);
+
+    [DllImport("shell32.dll")]
+    public static extern IntPtr ExtractAssociatedIcon(IntPtr hInst, StringBuilder lpIconPath, out ushort lpiIcon);
+}
+
+public static class NativeMethodHelpers
+{
+    public static string GetStringResource(string fileName, uint resourceId)
+    {
+        IntPtr? handle = null;
+        try
+        {
+            handle = WindowsNativeMethods.LoadLibrary(fileName);
+            StringBuilder buffer = new(8192); //Buffer for output from LoadString()
+            int length = WindowsNativeMethods.LoadString(handle.Value, resourceId, buffer, buffer.Capacity);
+            return buffer.ToString(0, length); //Return the part of the buffer that was used.
+        }
+        finally
+        {
+            if (handle is IntPtr validHandle)
+            {
+                WindowsNativeMethods.FreeLibrary(validHandle);
+            }
+        }
+    }
+
+    public static Icon GetIconResource(string fileName, uint resourceId)
+    {
+        IntPtr? handle = null;
+        try
+        {
+            handle = WindowsNativeMethods.LoadLibrary(fileName);
+            IntPtr handle2 = WindowsNativeMethods.LoadIcon(handle.Value, new IntPtr(resourceId));
+            return Icon.FromHandle(handle2);
+        }
+        finally
+        {
+            if (handle is IntPtr validHandle)
+            {
+                WindowsNativeMethods.FreeLibrary(validHandle);
+            }
+        }
+    }
+
+    /*public static Icon GetAssociatedIcon()
+    {
+        ushort uicon;
+        StringBuilder strB = new StringBuilder(fileName);
+        IntPtr handle = WindowsNativeMethods.ExtractAssociatedIcon(this.Handle, strB, out uicon);
+        return Icon.FromHandle(handle);
+    }*/
+}