C# winform 运行时可以调整大小和位置的文本框

1.使用鼠标控制位置：在任意位置点击左键拖动

2.使用鼠标控制大小：在控件右下角待变为‘调整光标’是可以调整大小

3.使用键盘控制位置：alt + 方向键

4.使用键盘控制大小：ctrl + 方向键

using System.ComponentModel;
 using System.Drawing;
 using System.Windows.Forms;


 namespace AppGenCode.Printer
 {


   public enum EnumAdjust
   {
     Nothing =0,
     Size = 1,
     Postion = 2
   }


   public partial class AdjustTextBox : TextBox
   {
     public AdjustTextBox()
     {
       InitializeComponent();
       InitCtrl();
     }


     public AdjustTextBox(IContainer container)
     {
       container.Add(this);
       InitializeComponent();
       InitCtrl();
     }


     private bool m_isMoving = false;
     private Point m_offset = new Point(0,0);
     private Size m_intSize = new Size(0, 0);
     private EnumAdjust m_adjust = EnumAdjust.Nothing;
     private int m_x, m_y, m_w, m_h = 0;


     private Rectangle RecAdjustSize
     {
       get { return new Rectangle(this.Width-15,this.Height-15,15,15);}
     }
     private Rectangle RecAdjustPostion
     {
       get { return new Rectangle(0, 0, this.Width, this.Height); }
     }


     private void InitCtrl()
     {
       this.Text = "asdf1234";
       this.Multiline = true;
       this.BorderStyle = BorderStyle.FixedSingle;
       this.ReadOnly = true;
     }
     #region 鼠标事件
     protected override void OnMouseDown(MouseEventArgs e)
     {
       m_isMoving = true;
       m_offset = new Point(e.X, e.Y);
       m_intSize.Width = this.Width;
       m_intSize.Height = this.Height;


       if (RecAdjustSize.Contains(e.X, e.Y)) //调整大小
       {
         this.Cursor = Cursors.SizeNWSE;
         m_adjust = EnumAdjust.Size;
       }
       else if (RecAdjustPostion.Contains(e.X, e.Y)) //调整位置
       {
         this.Cursor = Cursors.SizeAll;
         m_adjust = EnumAdjust.Postion;
       }
       else
       {
         m_adjust = EnumAdjust.Nothing;
       }
       base.OnMouseDown(e);
     }
     protected override void OnMouseUp(MouseEventArgs mevent)
     {
       Cursor = Cursors.Default;
       m_isMoving = false;
       
       base.OnMouseUp(mevent);
     }
     protected override void OnMouseMove(MouseEventArgs e)
     {
       CursorCtrl(e.X, e.Y);
       m_x = this.Left;
       m_y = this.Top;
       m_w = this.Width;
       m_h = this.Height;
       if (m_isMoving)
       {
         switch (m_adjust)
         {
           case EnumAdjust.Size:
             m_w = m_intSize.Width + (e.X - m_offset.X);
             m_h = m_intSize.Height + (e.Y - m_offset.Y);
             break;
           case EnumAdjust.Postion:
             m_x = Location.X + (e.X - m_offset.X);
             m_y = Location.Y + (e.Y - m_offset.Y);
             break;
         }
         BackColor = Color.Red;
         this.SetBounds(m_x, m_y, m_w, m_h);
       }
       base.OnMouseMove(e);
     }
     #endregion


     #region 键盘事件


     protected override void OnPreviewKeyDown(PreviewKeyDownEventArgs e)
     {
       base.OnPreviewKeyDown(e);
       if (e.Alt) //调整大小
       {
         switch (e.KeyCode)
         {
           case Keys.Left:
             this.Width -= 5;
             break;
           case Keys.Right:
             this.Width += 5;
             break;
           case Keys.Down:
             this.Height += 5;
             break;
           case Keys.Up:
             this.Height -= 5;
             break;
         }
         return;
       }
       if (e.Control)
       {
         switch (e.KeyCode) //调整位置
         {
           case Keys.Left:
             this.Left -= 5;
             break;
           case Keys.Right:
             this.Left += 5;
             break;
           case Keys.Up:
             this.Top -= 5;
             break;
           case Keys.Down:
             this.Top += 5;
             break;
         }
       }
     }
     #endregion


     private void CursorCtrl(int x,int y)
     {
       if (!m_isMoving && RecAdjustSize.Contains(x,y))
       {
         this.Cursor = Cursors.SizeNWSE;
         return;
       }
       this.Cursor = Cursors.Default;
     }
   }
 }