回答編集履歴

- 「文字入力支援君」はradianさんの言うようにおそらく、

- 1. 対象アプリをアクティブ化

- 1. クリップボードに文字をコピー

- 1. Ctrl+Vを送る

-

- という動作をしています。

-

- 対象アプリがアクティブ化したときにカーソルがない（ボタン等にフォーカスがある）と貼り付けられないので、特に入力エリアを探したりはしていなそうです（特定アプリに特別対応があるかもしれませんが）

-

- 最低限動作確認できるサンプルを作りました。

- ##### 使い方

- 1. 支援君のようにピンクの四角を対象アプリにドラッグ＆ドロップ

- 1. テキストボックスに何か入力

- 1. 貼り付けボタンを押す

-

- ##### 注意

- * エラーチェック一切なし

- * Word・Excelは手元にないので未確認

-

- Form1.cs

- ```C#

- using System;

- using System.Drawing;

- using System.Runtime.InteropServices;

- using System.Text;

- using System.Windows.Forms;

-

- namespace Questions252432

- {

- public partial class Form1 : Form

- {

- private IntPtr hWnd;

-

- public Form1() => InitializeComponent();

-

- private void Panel1_MouseDown(object sender, MouseEventArgs e)

- {

- if(e.Button == MouseButtons.Left) panel1.Capture = true;

- }

-

- private void Panel1_MouseUp(object sender, MouseEventArgs e)

- {

- panel1.Capture = false;

- var p = NativeMethods.GetCursorPos();

- var h = NativeMethods.WindowFromPoint(p);

- hWnd = NativeMethods.GetAncestor(h);

-

- label_title.Text = $"Title: {NativeMethods.GetWindowText(hWnd)}";

- label_class.Text = $"Class: {NativeMethods.GetClassName(hWnd)}";

- }

-

- private void Button1_Click(object sender, EventArgs e)

- {

- Clipboard.SetText(textBox1.Text);

- NativeMethods.SetForegroundWindow(hWnd);

- SendKeys.Send("^v");

- }

-

- private static class NativeMethods

- {

- [DllImport("user32")]

- private static extern bool GetCursorPos(out Point pPoint);

- public static Point GetCursorPos()

- {

- GetCursorPos(out var p);

- return p;

- }

-

- [DllImport("user32")]

- public static extern IntPtr WindowFromPoint(Point point);

-

- [DllImport("user32")]

- private static extern IntPtr GetAncestor(IntPtr hWnd, uint gaFlags);

- public static IntPtr GetAncestor(IntPtr hWnd) => GetAncestor(hWnd, GA_ROOTOWNER);

- private const uint GA_ROOTOWNER = 3;

-

- [DllImport("user32", CharSet = CharSet.Unicode)]

- private static extern int GetWindowText(IntPtr hWnd, StringBuilder lpString, int nMaxCount);

- public static string GetWindowText(IntPtr hWnd)

- {

- var sb = new StringBuilder(100);

- GetWindowText(hWnd, sb, sb.Capacity);

- return sb.ToString();

- }

-

- [DllImport("user32", CharSet = CharSet.Unicode)]

- private static extern int GetClassName(IntPtr hWnd, StringBuilder lpClassName, int nMaxCount);

- public static string GetClassName(IntPtr hWnd)

- {

- var sb = new StringBuilder(100);

- GetClassName(hWnd, sb, sb.Capacity);

- return sb.ToString();

- }

-

- [DllImport("user32")]

- public static extern bool SetForegroundWindow(IntPtr hWnd);

- }

- }

- }

- ```

-

- Form1.Designer.cs

- ```C#

- namespace Questions252432

- {

- partial class Form1

- {

- /// <summary>

- /// 必要なデザイナー変数です。

- /// </summary>

- private System.ComponentModel.IContainer components = null;

-

- /// <summary>

- /// 使用中のリソースをすべてクリーンアップします。

- /// </summary>

- /// <param name="disposing">マネージド リソースを破棄する場合は true を指定し、その他の場合は false を指定します。</param>

- protected override void Dispose(bool disposing)

- {

- if(disposing && (components != null))

- {

- components.Dispose();

- }

- base.Dispose(disposing);

- }

-

- #region Windows フォーム デザイナーで生成されたコード

-

- /// <summary>

- /// デザイナー サポートに必要なメソッドです。このメソッドの内容を

- /// コード エディターで変更しないでください。

- /// </summary>

- private void InitializeComponent()

- {

- this.button1 = new System.Windows.Forms.Button();

- this.label_title = new System.Windows.Forms.Label();

- this.label_class = new System.Windows.Forms.Label();

- this.textBox1 = new System.Windows.Forms.TextBox();

- this.panel1 = new System.Windows.Forms.Panel();

- this.SuspendLayout();

- //

- // button1

- //

- this.button1.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Right)));

- this.button1.Location = new System.Drawing.Point(297, 222);

- this.button1.Name = "button1";

- this.button1.Size = new System.Drawing.Size(75, 23);

- this.button1.TabIndex = 0;

- this.button1.Text = "貼り付け";

- this.button1.UseVisualStyleBackColor = true;

- this.button1.Click += new System.EventHandler(this.Button1_Click);

- //

- // label_title

- //

- this.label_title.AutoSize = true;

- this.label_title.Location = new System.Drawing.Point(54, 16);

- this.label_title.Name = "label_title";

- this.label_title.Size = new System.Drawing.Size(30, 12);

- this.label_title.TabIndex = 1;

- this.label_title.Text = "Title:";

- //

- // label_class

- //

- this.label_class.AutoSize = true;

- this.label_class.Location = new System.Drawing.Point(54, 31);

- this.label_class.Name = "label_class";

- this.label_class.Size = new System.Drawing.Size(36, 12);

- this.label_class.TabIndex = 2;

- this.label_class.Text = "Class:";

- //

- // textBox1

- //

- this.textBox1.AcceptsReturn = true;

- this.textBox1.AcceptsTab = true;

- this.textBox1.Anchor = ((System.Windows.Forms.AnchorStyles)((((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Bottom)

- | System.Windows.Forms.AnchorStyles.Left)

- | System.Windows.Forms.AnchorStyles.Right)));

- this.textBox1.Location = new System.Drawing.Point(12, 54);

- this.textBox1.Multiline = true;

- this.textBox1.Name = "textBox1";

- this.textBox1.Size = new System.Drawing.Size(360, 162);

- this.textBox1.TabIndex = 3;

- //

- // panel1

- //

- this.panel1.BackColor = System.Drawing.Color.FromArgb(((int)(((byte)(255)))), ((int)(((byte)(128)))), ((int)(((byte)(128)))));

- this.panel1.BorderStyle = System.Windows.Forms.BorderStyle.FixedSingle;

- this.panel1.Cursor = System.Windows.Forms.Cursors.Cross;

- this.panel1.Location = new System.Drawing.Point(12, 12);

- this.panel1.Name = "panel1";

- this.panel1.Size = new System.Drawing.Size(36, 36);

- this.panel1.TabIndex = 4;

- this.panel1.MouseDown += new System.Windows.Forms.MouseEventHandler(this.Panel1_MouseDown);

- this.panel1.MouseUp += new System.Windows.Forms.MouseEventHandler(this.Panel1_MouseUp);

- //

- // Form1

- //

- this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 12F);

- this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;

- this.ClientSize = new System.Drawing.Size(384, 257);

- this.Controls.Add(this.panel1);

- this.Controls.Add(this.textBox1);

- this.Controls.Add(this.label_class);

- this.Controls.Add(this.label_title);

- this.Controls.Add(this.button1);

- this.Name = "Form1";

- this.Text = "貼り付けくん";

- this.ResumeLayout(false);

- this.PerformLayout();

-

- }

-

- #endregion

-

- private System.Windows.Forms.Button button1;

- private System.Windows.Forms.Label label_title;

- private System.Windows.Forms.Label label_class;

- private System.Windows.Forms.TextBox textBox1;

- private System.Windows.Forms.Panel panel1;

- }

- }

- ```

- 

-

- ---

-