How to move and resize a form without a border?

- Form의 BorderStyle을 Node으로 하면 Border가 사라진다.

- 그러면 Resize 기능도 사라진다.

- 이런 경우 Grip을 실시간 추가 하고 OnPaint로 그려주면 Resize Grip을 이용 Resize가 가능하다.

- 단, Form을 다른 콘트롤이 꽉 채우게 되면 Resizing Grip이 Background로 그려지기 때문에 보이지를 않으므로 주의한다.

출처 :

https://stackoverflow.com/questions/2575216/how-to-move-and-resize-a-form-without-a-border

How to move and resize a form without a border?

public FormMain()         {                            InitializeComponent();             this.FormBorderStyle = FormBorderStyle.None;             this.DoubleBuffered = true;             this.SetStyle(ControlStyles.ResizeRedraw, true);         }         private const int cGrip = 16;      // Grip size         private const int cCaption = 32;   // Caption bar height;         protected override void OnPaint(PaintEventArgs e)         {             Rectangle rc = new Rectangle(this.ClientSize.Width - cGrip, this.ClientSize.Height - cGrip, cGrip, cGrip);             ControlPaint.DrawSizeGrip(e.Graphics, this.BackColor, rc);             rc = new Rectangle(0, 0, this.ClientSize.Width, cCaption);             e.Graphics.FillRectangle(Brushes.DarkBlue, rc);         }         protected override void WndProc(ref Message m)         {             if (m.Msg == 0x84)             {  // Trap WM_NCHITTEST                 Point pos = new Point(m.LParam.ToInt32());                 pos = this.PointToClient(pos);                 if (pos.Y < cCaption)                 {                     m.Result = (IntPtr)2;  // HTCAPTION                     return;                 }                 if (pos.X >= this.ClientSize.Width - cGrip && pos.Y >= this.ClientSize.Height - cGrip)                 {                     m.Result = (IntPtr)17; // HTBOTTOMRIGHT                     return;                 }             }             base.WndProc(ref m);         }         ///////////////////////////////////////////