C#可以自由移动和伸缩的TextBox

效果图 

主体代码

using System;
using System.Collections.Generic;
using System.Drawing;
using System.Windows.Forms;

namespace FrameControl
{
    public partial class MoveTextBox : UserControl
    {
        /// <summary>
        /// 鼠标点击该控件时的事件
        /// </summary>
        public event Action<object, EventArgs> CtrMouseClick;


        public event Action<object, KeyEventArgs> CtrKeyDown;
        enum MousePosOnCtrl
        {
            NONE = 0,
            TOP = 1,
            RIGHT = 2,
            BOTTOM = 3,
            LEFT = 4,
            TOPLEFT = 5,
            TOPRIGHT = 6,
            BOTTOMLEFT = 7,
            BOTTOMRIGHT = 8,
        }

        Dictionary<Panel, MousePosOnCtrl> _dictPanl = new Dictionary<Panel, MousePosOnCtrl>();
        MousePosOnCtrl _mpoc;  //鼠标在控件中位置
        const int MinWidth = 20; //最小宽度
        const int MinHeight = 20;//最小高度

        public TextBox TextBox
        {
            get { return this.textBox1; }
            set { this.textBox1 = value; }
        }

        public MoveTextBox()
        {
            InitializeComponent();
            _dictPanl[this.panelTL] = MousePosOnCtrl.TOPLEFT;
            _dictPanl[this.panelT] = MousePosOnCtrl.TOP;
            _dictPanl[this.panelTR] = MousePosOnCtrl.TOPRIGHT;
            _dictPanl[this.panelL] = MousePosOnCtrl.LEFT;
            _dictPanl[this.panelR] = MousePosOnCtrl.RIGHT;
            _dictPanl[this.panelBL] = MousePosOnCtrl.BOTTOMLEFT;
            _dictPanl[this.panelB] = MousePosOnCtrl.BOTTOM;
            _dictPanl[this.panelBR] = MousePosOnCtrl.BOTTOMRIGHT;
            foreach (var kv in _dictPanl)
            {
                kv.Key.BringToFront();
                kv.Key.MouseMove += Panel_MouseMove;
                kv.Key.MouseLeave += Panel_MouseLeave;
                kv.Key.MouseDown += Panel_MouseDown;
            }
            SetControlEnabled(this.textBox1, false);
            boundVisible(false);
        }


        Point _lastLocation; //上个鼠标坐标
        Size _lastSize;
        private void Panel_MouseDown(object sender, MouseEventArgs e)
        {
            _lastMousePoint = Cursor.Position;
            _lastLocation = this.Location;
            _lastSize = this.Size;
        }

        bool SetCursorShape(int x, int y)
        {
            switch (_mpoc)
            {
                case MousePosOnCtrl.TOPLEFT:
                case MousePosOnCtrl.BOTTOMRIGHT:
                    Cursor.Current = Cursors.SizeNWSE;  //左上
                    break;
                case MousePosOnCtrl.TOPRIGHT:
                case MousePosOnCtrl.BOTTOMLEFT:
                    Cursor.Current = Cursors.SizeNESW;  //右上
                    break;
                case MousePosOnCtrl.TOP:
                case MousePosOnCtrl.BOTTOM:
                    Cursor.Current = Cursors.SizeNS;  //上
                    break;
                case MousePosOnCtrl.LEFT:
                case MousePosOnCtrl.RIGHT:
                    Cursor.Current = Cursors.SizeWE;  //左
                    break;
                default:
                    Cursor.Current = Cursors.SizeAll;
                    break;
            }
            return true;
        }

        void ControlMove()
        {
            Point currMousePoint = Cursor.Position;
            int x = currMousePoint.X - _lastMousePoint.X;
            int y = currMousePoint.Y - _lastMousePoint.Y;
            switch (this._mpoc)
            {
                case MousePosOnCtrl.TOP:
                    this.Top = _lastLocation.Y + y;
                    this.Height = _lastSize.Height - y;
                    Cursor.Current = Cursors.SizeNS;  //上
                    break;
                case MousePosOnCtrl.BOTTOM:
                    this.Height = _lastSize.Height + y;
                    Cursor.Current = Cursors.SizeNS;  //上
                    break;
                case MousePosOnCtrl.LEFT:
                    this.Left = _lastLocation.X + x;
                    this.Width = _lastSize.Width - x;
                    Cursor.Current = Cursors.SizeWE;  //左
                    break;
                case MousePosOnCtrl.RIGHT:
                    this.Width = _lastSize.Width + x;
                    Cursor.Current = Cursors.SizeWE;  //左
                    break;
                case MousePosOnCtrl.TOPLEFT:
                    this.Top = _lastLocation.Y + y;
                    this.Height = _lastSize.Height - y;
                    this.Left = _lastLocation.X + x;
                    this.Width = _lastSize.Width - x;
                    Cursor.Current = Cursors.SizeNWSE;  //左上
                    break;
                case MousePosOnCtrl.TOPRIGHT:
                    this.Top = _lastLocation.Y + y;
                    this.Height = _lastSize.Height - y;
                    this.Width = _lastSize.Width + x;
                    Cursor.Current = Cursors.SizeNESW;  //右上
                    break;
                case MousePosOnCtrl.BOTTOMLEFT:
                    this.Height = _lastSize.Height + y;
                    this.Left = _lastLocation.X + x;
                    this.Width = _lastSize.Width - x;
                    Cursor.Current = Cursors.SizeNESW;  //右上
                    break;
                case MousePosOnCtrl.BOTTOMRIGHT:
                    this.Width = _lastSize.Width + x;
                    this.Height = _lastSize.Height + y;
                    Cursor.Current = Cursors.SizeNWSE;  //左上
                    break;
                default:
                    Cursor.Current = Cursors.SizeAll;
                    break;

            }
        }

        private void Panel_MouseLeave(object sender, EventArgs e)
        {
            Cursor.Current = Cursors.Default;
            _mpoc = MousePosOnCtrl.NONE;
        }

        private void Panel_MouseMove(object sender, MouseEventArgs e)
        {
            Panel p = sender as Panel;
            _mpoc = _dictPanl[p];
            SetCursorShape(e.X, e.Y);
            if (e.Button == MouseButtons.Left)
            {
                ControlMove();
            }
        }

        void boundVisible(bool isVisible)
        {
            this.panelContain.BorderStyle = isVisible ? BorderStyle.FixedSingle : BorderStyle.None;
            foreach (var kv in _dictPanl)
            {
                kv.Key.Visible = isVisible;
            }
        }

        bool _tbEnable = false;
        /// <summary>
        /// 使该控件具有焦点，可以输入信息
        /// </summary>
        /// <param name="focus"></param>
        public void SetFocus(bool focus)
        {
            boundVisible(focus);
            if (!focus)
            {
                if (_tbEnable)
                {
                    SetControlEnabled(this.textBox1, false);
                    _tbEnable = false;
                }
            }
        }

        private void UserControl1_MouseDoubleClick(object sender, MouseEventArgs e)
        {
            if (!_tbEnable)
            {
                SetControlEnabled(this.textBox1, true);
                _tbEnable = true;
            }
            boundVisible(false);
        }

        Point _lastMousePoint; //上个鼠标坐标
        private void MoveCtr_MouseDown(object sender, MouseEventArgs e)
        {
            boundVisible(true);
            _lastMousePoint = Cursor.Position;
            if (CtrMouseClick != null)
            {
                CtrMouseClick(this, e);
            }
        }

        private void MoveCtr_MouseMove(object sender, MouseEventArgs e)
        {
            Point curPoint = Cursor.Position;
            if (e.Button == MouseButtons.Left)
            {
                if (_mpoc == MousePosOnCtrl.NONE)
                {
                    Cursor.Current = Cursors.SizeAll;
                    int x = curPoint.X - _lastMousePoint.X;
                    int y = curPoint.Y - _lastMousePoint.Y;
                    this.Location = new Point(this.Location.X + x, this.Location.Y + y);
                    _lastMousePoint = curPoint;
                    this.BringToFront();
                }
            }
        }

        private void MoveTB_KeyDown(object sender, KeyEventArgs e)
        {
            switch (e.KeyCode)
            {
                case Keys.Up:
                    this.Top += 1;
                    break;
                case Keys.Down:
                    this.Top -= 1;
                    break;
                case Keys.Left:
                    this.Left -= 1;
                    break;
                case Keys.Right:
                    this.Left += 1;
                    break;
            }
            if (CtrKeyDown != null)
            {
                CtrKeyDown(this, e);
            }
        }

        /// <summary>
        /// 复制该控件的基本信息
        /// </summary>
        /// <returns></returns>
        public MoveTextBox Copy()
        {
            MoveTextBox moveTB = new MoveTextBox();
            moveTB.TextBox.Font = this.textBox1.Font;
            moveTB.TextBox.ForeColor = this.textBox1.ForeColor;
            moveTB.TextBox.BackColor = this.textBox1.BackColor;
            moveTB.TextBox.Text = this.textBox1.Text;
            moveTB.BackgroundImage = this.BackgroundImage;
            return moveTB;
        }

        [System.Runtime.InteropServices.DllImport("user32.dll ")]
        static extern int SetWindowLong(IntPtr hWnd, int nIndex, int wndproc);
        [System.Runtime.InteropServices.DllImport("user32.dll ")]
        static extern int GetWindowLong(IntPtr hWnd, int nIndex);

        const int GWL_STYLE = -16;
        const int WS_DISABLED = 0x8000000;

        public static void SetControlEnabled(Control c, bool enabled)
        {
            if (enabled)
            {
                SetWindowLong(c.Handle, GWL_STYLE, (~WS_DISABLED) & GetWindowLong(c.Handle, GWL_STYLE));
            }
            else
            {
                SetWindowLong(c.Handle, GWL_STYLE, WS_DISABLED + GetWindowLong(c.Handle, GWL_STYLE));
            }
        }


    }
}

设计器代码 

namespace FrameControl
{
    partial class MoveTextBox
    {
        /// <summary> 
        /// 必需的设计器变量。
        /// </summary>
        private System.ComponentModel.IContainer components = null;

        /// <summary> 
        /// 清理所有正在使用的资源。
        /// </summary>
        /// <param name="disposing">如果应释放托管资源，为 true；否则为 false。</param>
        protected override void Dispose(bool disposing)
        {
            if (disposing && (components != null))
            {
                components.Dispose();
            }
            base.Dispose(disposing);
        }

        #region 组件设计器生成的代码

        /// <summary> 
        /// 设计器支持所需的方法 - 不要修改
        /// 使用代码编辑器修改此方法的内容。
        /// </summary>
        private void InitializeComponent()
        {
            this.panelContain = new System.Windows.Forms.Panel();
            this.textBox1 = new System.Windows.Forms.TextBox();
            this.panelR = new System.Windows.Forms.Panel();
            this.panelBR = new System.Windows.Forms.Panel();
            this.panelB = new System.Windows.Forms.Panel();
            this.panelBL = new System.Windows.Forms.Panel();
            this.panelL = new System.Windows.Forms.Panel();
            this.panelTR = new System.Windows.Forms.Panel();
            this.panelTL = new System.Windows.Forms.Panel();
            this.panelT = new System.Windows.Forms.Panel();
            this.panelContain.SuspendLayout();
            this.SuspendLayout();
            // 
            // panelContain
            // 
            this.panelContain.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.panelContain.Controls.Add(this.textBox1);
            this.panelContain.Location = new System.Drawing.Point(2, 2);
            this.panelContain.Name = "panelContain";
            this.panelContain.Size = new System.Drawing.Size(146, 26);
            this.panelContain.TabIndex = 0;
            this.panelContain.MouseDoubleClick += new System.Windows.Forms.MouseEventHandler(this.UserControl1_MouseDoubleClick);
            this.panelContain.MouseDown += new System.Windows.Forms.MouseEventHandler(this.MoveCtr_MouseDown);
            this.panelContain.MouseMove += new System.Windows.Forms.MouseEventHandler(this.MoveCtr_MouseMove);
            // 
            // textBox1
            // 
            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.BackColor = System.Drawing.Color.White;
            this.textBox1.BorderStyle = System.Windows.Forms.BorderStyle.None;
            this.textBox1.Font = new System.Drawing.Font("宋体", 15F, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, ((byte)(134)));
            this.textBox1.Location = new System.Drawing.Point(0, 0);
            this.textBox1.Multiline = true;
            this.textBox1.Name = "textBox1";
            this.textBox1.Size = new System.Drawing.Size(146, 26);
            this.textBox1.TabIndex = 35;
            this.textBox1.Text = "New Item";
            this.textBox1.TextAlign = System.Windows.Forms.HorizontalAlignment.Center;
            // 
            // panelR
            // 
            this.panelR.Anchor = System.Windows.Forms.AnchorStyles.Right;
            this.panelR.BackColor = System.Drawing.SystemColors.ActiveCaptionText;
            this.panelR.Location = new System.Drawing.Point(145, 13);
            this.panelR.Name = "panelR";
            this.panelR.Size = new System.Drawing.Size(5, 5);
            this.panelR.TabIndex = 33;
            // 
            // panelBR
            // 
            this.panelBR.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Right)));
            this.panelBR.BackColor = System.Drawing.SystemColors.ActiveCaptionText;
            this.panelBR.Location = new System.Drawing.Point(145, 25);
            this.panelBR.Name = "panelBR";
            this.panelBR.Size = new System.Drawing.Size(5, 5);
            this.panelBR.TabIndex = 32;
            // 
            // panelB
            // 
            this.panelB.Anchor = System.Windows.Forms.AnchorStyles.Bottom;
            this.panelB.BackColor = System.Drawing.SystemColors.ActiveCaptionText;
            this.panelB.Location = new System.Drawing.Point(73, 25);
            this.panelB.Name = "panelB";
            this.panelB.Size = new System.Drawing.Size(5, 5);
            this.panelB.TabIndex = 31;
            // 
            // panelBL
            // 
            this.panelBL.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Left)));
            this.panelBL.BackColor = System.Drawing.SystemColors.ActiveCaptionText;
            this.panelBL.Location = new System.Drawing.Point(0, 25);
            this.panelBL.Name = "panelBL";
            this.panelBL.Size = new System.Drawing.Size(5, 5);
            this.panelBL.TabIndex = 30;
            // 
            // panelL
            // 
            this.panelL.Anchor = System.Windows.Forms.AnchorStyles.Left;
            this.panelL.BackColor = System.Drawing.SystemColors.ActiveCaptionText;
            this.panelL.Location = new System.Drawing.Point(0, 13);
            this.panelL.Name = "panelL";
            this.panelL.Size = new System.Drawing.Size(5, 5);
            this.panelL.TabIndex = 27;
            // 
            // panelTR
            // 
            this.panelTR.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Right)));
            this.panelTR.BackColor = System.Drawing.SystemColors.ActiveCaptionText;
            this.panelTR.Location = new System.Drawing.Point(145, 0);
            this.panelTR.Name = "panelTR";
            this.panelTR.Size = new System.Drawing.Size(5, 5);
            this.panelTR.TabIndex = 29;
            // 
            // panelTL
            // 
            this.panelTL.BackColor = System.Drawing.SystemColors.ActiveCaptionText;
            this.panelTL.Location = new System.Drawing.Point(0, 0);
            this.panelTL.Name = "panelTL";
            this.panelTL.Size = new System.Drawing.Size(5, 5);
            this.panelTL.TabIndex = 28;
            // 
            // panelT
            // 
            this.panelT.Anchor = System.Windows.Forms.AnchorStyles.Top;
            this.panelT.BackColor = System.Drawing.SystemColors.ActiveCaptionText;
            this.panelT.Location = new System.Drawing.Point(73, 0);
            this.panelT.Name = "panelT";
            this.panelT.Size = new System.Drawing.Size(5, 5);
            this.panelT.TabIndex = 26;
            // 
            // MoveTB
            // 
            this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 12F);
            this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
            this.BackColor = System.Drawing.Color.Transparent;
            this.BackgroundImageLayout = System.Windows.Forms.ImageLayout.Zoom;
            this.Controls.Add(this.panelR);
            this.Controls.Add(this.panelBR);
            this.Controls.Add(this.panelB);
            this.Controls.Add(this.panelBL);
            this.Controls.Add(this.panelL);
            this.Controls.Add(this.panelTR);
            this.Controls.Add(this.panelTL);
            this.Controls.Add(this.panelT);
            this.Controls.Add(this.panelContain);
            this.Name = "MoveTB";
            this.Size = new System.Drawing.Size(150, 30);
            this.KeyDown += new System.Windows.Forms.KeyEventHandler(this.MoveTB_KeyDown);
            this.panelContain.ResumeLayout(false);
            this.panelContain.PerformLayout();
            this.ResumeLayout(false);

        }

        #endregion

        private System.Windows.Forms.Panel panelContain;
        private System.Windows.Forms.Panel panelR;
        private System.Windows.Forms.Panel panelBR;
        private System.Windows.Forms.Panel panelB;
        private System.Windows.Forms.Panel panelBL;
        private System.Windows.Forms.Panel panelL;
        private System.Windows.Forms.Panel panelTR;
        private System.Windows.Forms.Panel panelTL;
        private System.Windows.Forms.Panel panelT;
        private System.Windows.Forms.TextBox textBox1;
    }
}

 样例下载

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