tweaks to handle unicode paths

tweaks to handle unicode paths

.

.gitignore

@@ -5,3 +5,5 @@
 /bin
 /obj
 /.vs
+/Properties/PublishProfiles/StandaloneExeToFolder.pubxml.user
+/SingleInstanceAccumulator.csproj.user

MessageForm.cs

@@ -24,7 +24,6 @@ public SingleInstanceMessageForm(string windowTitle, Action<string> onNewValue,
             WindowState = FormWindowState.Minimized;
         }
 
-        //private void Form1_Load(object sender, EventArgs e)
         protected override void OnLoad(EventArgs e)
         {
             Win32.CHANGEFILTERSTRUCT changeFilter = new();
@@ -54,17 +53,15 @@ protected override void WndProc(ref Message m)
             {
                 // Extract the file name
                 Win32.COPYDATASTRUCT copyData = (Win32.COPYDATASTRUCT)Marshal.PtrToStructure(m.LParam, typeof(Win32.COPYDATASTRUCT));
-                int dataType = (int)copyData.dwData;
-                if (dataType == 2)
+                if (copyData.dwData == (Win32.WM_USER + 1))
                 {
-                    string fileName = Marshal.PtrToStringAnsi(copyData.lpData);
                     Timer.Interval = TimeoutMillisecs; //this is a timer "reset"
-                    OnNewValue(fileName);
+                    OnNewValue(copyData.lpData);
                     //MessageBox.Show($"received: {fileName}", "SingleInstanceArgAggregator", MessageBoxButtons.OK, MessageBoxIcon.Error);
                 }
                 else
                 {
-                    MessageBox.Show(String.Format("Unrecognized data type = {0}.", dataType), "SingleInstanceArgAggregator", MessageBoxButtons.OK, MessageBoxIcon.Error);
+                    MessageBox.Show($"Unrecognized message id, expecting {Win32.WM_USER + 1}, got {copyData.dwData}.");
                 }
             }
             else
@@ -87,39 +84,29 @@ public static bool SendStringToWindow(string windowTitle, string data)
 
             if (retries == 0)
             {
-                MessageBox.Show($"Couldn't find window named: {windowTitle}", "SingleInstanceArgAggregator", MessageBoxButtons.OK, MessageBoxIcon.Error);
+                MessageBox.Show($"Couldn't find window named: {windowTitle}");
                 return false;
             }
 
-            var ptrCopyData = IntPtr.Zero;
+            //good example of COPYDATA + SendMessage: https://forum.strokesplus.net/posts/t6052-Using-Windows-Messages--WM-COPYDATA--to-Execute-Scripts
             try
             {
                 // Create the data structure and fill with data
                 Win32.COPYDATASTRUCT copyData = new Win32.COPYDATASTRUCT
                 {
-                    dwData = new IntPtr(2),    // Just a number to identify the data type
-                    cbData = data.Length + 1,  // One extra byte for the \0 character
-                    lpData = Marshal.StringToHGlobalAnsi(data)
+                    dwData = new IntPtr(Win32.WM_USER + 1),    // Just an arbitrary number to make sure we're getting our specific message on the other side
+                    cbData = System.Text.Encoding.Unicode.GetBytes(data).Length + 1,  // One extra byte for the \0 character
+                    lpData = data
                 };
 
-                // Allocate memory for the data and copy
-                ptrCopyData = Marshal.AllocCoTaskMem(Marshal.SizeOf(copyData));
-                Marshal.StructureToPtr(copyData, ptrCopyData, false);
-
                 // Send the message
-                Win32.SendMessage(ptrWnd, Win32.WM_COPYDATA, IntPtr.Zero, ptrCopyData);
+                Win32.SendMessage(ptrWnd, Win32.WM_COPYDATA, IntPtr.Zero, ref copyData);
             }
             catch (Exception ex)
             {
                 MessageBox.Show(ex.ToString(), windowTitle, MessageBoxButtons.OK, MessageBoxIcon.Error);
                 return false;
             }
-            finally
-            {
-                // Free the allocated memory after the contol has been returned
-                if (ptrCopyData != IntPtr.Zero)
-                    Marshal.FreeCoTaskMem(ptrCopyData);
-            }
 
             return true;
 

SingleInstanceAccumulator.csproj

@@ -6,6 +6,10 @@
 	  <Nullable>enable</Nullable>
 	  <UseWindowsForms>true</UseWindowsForms>
 	  <ImplicitUsings>enable</ImplicitUsings>
+	  <RepositoryUrl>https://github.com/Beej126/SingleInstanceAccumulator</RepositoryUrl>
+	  <PackageProjectUrl>https://github.com/Beej126/SingleInstanceAccumulator</PackageProjectUrl>
+	  <AssemblyVersion>1.0.0.4</AssemblyVersion>
+	  <FileVersion>1.0.0.4</FileVersion>
   </PropertyGroup>
   <ItemGroup>
     <Compile Update="MessageForm.cs" />

Win32.cs

@@ -32,26 +32,31 @@ public abstract partial class Win32
     /// </summary>
     public static uint WM_COPYDATA = 0x004A;
 
+    /// <summary>
+    /// The WM_USER constant is used by applications to help define private messages for use by private window classes, usually of the form WM_USER+X, where X is an integer value.
+    /// </summary>
+    public static uint WM_USER = 0x0400;
+
     /// <summary>
     /// Contains data to be passed to another application by the WM_COPYDATA message.
     /// </summary>
-    [StructLayout(LayoutKind.Sequential)]
     public struct COPYDATASTRUCT
     {
-      /// <summary>
-      /// The data to be passed to the receiving application. This member can be IntPtr.Zero.
-      /// </summary>
-      public IntPtr dwData;
-
-      /// <summary>
-      /// The size, in bytes, of the data pointed to by the lpData member.
-      /// </summary>
-      public int cbData;
-
-      /// <summary>
-      /// The data to be passed to the receiving application. This member can be IntPtr.Zero.
-      /// </summary>
-      public IntPtr lpData;
+        /// <summary>
+        /// The data to be passed to the receiving application. This member can be IntPtr.Zero.
+        /// </summary>
+        public IntPtr dwData;
+
+        /// <summary>
+        /// The size, in bytes, of the data pointed to by the lpData member.
+        /// </summary>
+        public int cbData;
+
+        /// <summary>
+        /// The data to be passed to the receiving application. This member can be IntPtr.Zero.
+        /// </summary>
+        [System.Runtime.InteropServices.MarshalAs(System.Runtime.InteropServices.UnmanagedType.LPWStr)]
+        public string lpData;
     }
 
     /// <summary>
@@ -63,7 +68,7 @@ public struct COPYDATASTRUCT
     /// <param name="lParam">Additional message-specific information.</param>
     /// <returns>The return value specifies the result of the message processing; it depends on the message sent.</returns>
     [DllImport("user32.dll", CharSet = CharSet.Unicode)]
-    public static extern IntPtr SendMessage(IntPtr hWnd, UInt32 Msg, IntPtr wParam, IntPtr lParam);
+    public static extern IntPtr SendMessage(IntPtr hWnd, UInt32 Msg, IntPtr wParam, ref COPYDATASTRUCT lParam);
 
     /// <summary>
     /// Values used in the struct CHANGEFILTERSTRUCT