真似る対象

本当にクリップボードにコピーされたかどうかの不安を解消するためのツール

ソース

ClipMon.cs

using System;
using System.Drawing;
using System.Runtime.InteropServices;
using System.Windows.Forms;

public class ClipMon : Form
{
    private static class NativeMethods
    {
        public const int WM_CLIPBOARDUPDATE = 0x031D;

        [DllImport("user32.dll", SetLastError = true)]
        [return: MarshalAs(UnmanagedType.Bool)]
        public static extern bool AddClipboardFormatListener(IntPtr hwnd);

        [DllImport("user32.dll", SetLastError = true)]
        [return: MarshalAs(UnmanagedType.Bool)]
        public static extern bool RemoveClipboardFormatListener(IntPtr hwnd);
    }

    public ClipMon()
    {
        // 隠しウィンドウとして設定
        this.ShowInTaskbar = false;
        this.WindowState = FormWindowState.Minimized;
        this.Load += (s, e) => { 
            this.Size = Size.Empty;
            NativeMethods.AddClipboardFormatListener(this.Handle);
        };
        this.FormClosed += (s, e) => NativeMethods.RemoveClipboardFormatListener(this.Handle);
    }

    protected override void WndProc(ref Message m)
    {
        if (m.Msg == NativeMethods.WM_CLIPBOARDUPDATE)
        {
            try
            {
                if (Clipboard.ContainsText())
                {
                    string text = Clipboard.GetText();
                    ShowToast(text);
                }
            }
            catch (Exception ex)
            {
                Console.WriteLine($"クリップボード取得エラー: {ex.Message}");
            }
        }
        base.WndProc(ref m);
    }

    private void ShowToast(string text)
    {
        ToastForm toast = new ToastForm(text, 3000);
        toast.Show();
    }

    [STAThread]
    public static void Main()
    {
        Application.EnableVisualStyles();
        Application.SetCompatibleTextRenderingDefault(false);
        Application.Run(new ClipMon());
    }
}

public class ToastForm : Form
{
    private System.Windows.Forms.Timer closeTimer;

    public ToastForm(string text, int duration)
    {
        this.FormBorderStyle = FormBorderStyle.None;
        this.ShowInTaskbar = false;
        this.StartPosition = FormStartPosition.Manual;
        this.BackColor = Color.FromArgb(51, 51, 51);
        this.TopMost = true;

        Label label = new Label();
        label.Text = text;
        label.ForeColor = Color.White;
        label.Font = new Font("Meiryo", 12F, FontStyle.Regular, GraphicsUnit.Point, ((byte)(128)));
        label.Location = new Point(18, 12);
        label.AutoSize = true;
        this.Controls.Add(label);

        // 画面サイズと最大サイズを計算
        Rectangle workingArea = Screen.PrimaryScreen.WorkingArea;
        int maxWidth = (int)(workingArea.Width / 2.8);
        int maxHeight = (int)(workingArea.Height / 8.0);

        label.MaximumSize = new Size(maxWidth, maxHeight);

        // サイズと位置を調整
        this.ClientSize = new Size(label.PreferredWidth + 36, label.PreferredHeight + 24);
        this.Location = new Point(workingArea.Right - this.Width - 32, workingArea.Bottom - this.Height - 48);

        closeTimer = new System.Windows.Forms.Timer();
        closeTimer.Interval = duration;
        closeTimer.Tick += (s, e) => { this.Close(); };
        closeTimer.Start();
    }

    protected override void Dispose(bool disposing)
    {
        if (disposing && (closeTimer != null))
        {
            closeTimer.Dispose();
        }
        base.Dispose(disposing);
    }
}

clipmon.csproj

<Project Sdk="Microsoft.NET.Sdk">
  <PropertyGroup>
    <OutputType>WinExe</OutputType>
    <TargetFramework>net8.0-windows</TargetFramework>
    <UseWindowsForms>true</UseWindowsForms>
    <ImplicitUsings>enable</ImplicitUsings>
    <Nullable>enable</Nullable>
  </PropertyGroup>
</Project>

ビルド方法

dotnet build

出来上がり

│  ClipMon.cs
│  clipmon.csproj
│
├─bin
│  └─Debug
│      └─net8.0-windows
│              clipmon.deps.json
│              clipmon.dll
│              clipmon.exe
│              clipmon.pdb
│              clipmon.runtimeconfig.json
│
└─obj
    │  clipmon.csproj.nuget.dgspec.json
    │  clipmon.csproj.nuget.g.props
    │  clipmon.csproj.nuget.g.targets
    │  project.assets.json
    │  project.nuget.cache
    │
    └─Debug
        └─net8.0-windows
            │  .NETCoreApp,Version=v8.0.AssemblyAttributes.cs
            │  apphost.exe
            │  clipmon.AssemblyInfo.cs
            │  clipmon.AssemblyInfoInputs.cache
            │  clipmon.assets.cache
            │  clipmon.csproj.CoreCompileInputs.cache
            │  clipmon.csproj.FileListAbsolute.txt
            │  clipmon.dll
            │  clipmon.GeneratedMSBuildEditorConfig.editorconfig
            │  clipmon.genruntimeconfig.cache
            │  clipmon.GlobalUsings.g.cs
            │  clipmon.pdb
            │
            ├─ref
            │      clipmon.dll
            │
            └─refint
                    clipmon.dll

実行してみた図

※コピーした、「net8.0-windows」という文字列が右下に出ている