给shape控件加上运行时改变大小的特性（帮忙找找错误谢谢）。(100分)

如题：
代码如下：
unit mshape1;

interface

uses
Windows, Messages, SysUtils, Classes, Controls, ExtCtrls;

const
sc_DragMove: Longint = $F012;
type
Tmshape1 = class(tshape)
private
{ Private declarations }
protected
{ Protected declarations }
public
procedure WmNcHitTest (var Msg: TWmNcHitTest);
message wm_NcHitTest;
{ Public declarations }
published
{ Published declarations }
end;

TDdhSizerControl = class (TCustomControl)
private
FControl: TControl;
FRectList: array [1..8] of TRect;
FPosList: array [1..8] of Integer;
public
constructor Create (AOwner: TComponent;
AControl: TControl);
procedure CreateParams (var Params: TCreateParams);
override;
procedure CreateHandle; override;
procedure WmNcHitTest (var Msg: TWmNcHitTest);
message wm_NcHitTest;
procedure WmSize (var Msg: TWmSize);
message wm_Size;
procedure WmLButtonDown (var Msg: TWmLButtonDown);
message wm_LButtonDown;
procedure WmMove (var Msg: TWmMove);
message wm_Move;
procedure Paint; override;
procedure SizerControlExit (Sender: TObject);
end;

procedure Register;

implementation

uses
Graphics;

// TDdhSizeButton methods

procedure Tmshape1.WmNcHitTest(var Msg: TWmNcHitTest);
var
Pt: TPoint;
begin
Pt := Point (Msg.XPos, Msg.YPos);
Pt := ScreenToClient (Pt);
if (Pt.x < 5) and (pt.y < 5) then
Msg.Result := htTopLeft
else if (Pt.x > Width - 5) and (pt.y < 5) then
Msg.Result := htTopRight
else if (Pt.x > Width - 5) and (pt.y > Height - 5) then
Msg.Result := htBottomRight
else if (Pt.x < 5) and (pt.y > Height - 5) then
Msg.Result := htBottomLeft
else if (Pt.x < 5) then
Msg.Result := htLeft
else if (pt.y < 5) then
Msg.Result := htTop
else if (Pt.x > Width - 5) then
Msg.Result := htRight
else if (pt.y > Height - 5) then
Msg.Result := htBottom
else
inherited;
end;

// TDdhSizerControl methods

constructor TDdhSizerControl.Create (
AOwner: TComponent; AControl: TControl);
var
R: TRect;
begin
inherited Create (AOwner);
FControl := AControl;
// install the new handler
OnExit := SizerControlExit;
// set the size and position
R := FControl.BoundsRect;
InflateRect (R, 2, 2);
BoundsRect := R;
// set the parent
Parent := FControl.Parent;
// create the list of positions
FPosList [1] := htTopLeft;
FPosList [2] := htTop;
FPosList [3] := htTopRight;
FPosList [4] := htRight;
FPosList [5] := htBottomRight;
FPosList [6] := htBottom;
FPosList [7] := htBottomLeft;
FPosList [8] := htLeft;
end;

procedure TDdhSizerControl.CreateHandle;
begin
inherited CreateHandle;
SetFocus;
end;

procedure TDdhSizerControl.CreateParams (var Params: TCreateParams);
begin
inherited CreateParams(Params);
Params.ExStyle := Params.ExStyle +
ws_ex_Transparent;
end;

procedure TDdhSizerControl.Paint;
var
I: Integer;
begin
Canvas.Brush.Color := clBlack;
for I := 1 to 8 do
Canvas.Rectangle (FRectList .Left, FRectList .Top,
FRectList .Right, FRectList .Bottom);
end;

procedure TDdhSizerControl.WmNcHitTest(var Msg: TWmNcHitTest);
var
Pt: TPoint;
I: Integer;
begin
Pt := Point (Msg.XPos, Msg.YPos);
Pt := ScreenToClient (Pt);
Msg.Result := 0;
for I := 1 to 8 do
if PtInRect (FRectList , Pt) then
Msg.Result := FPosList ;
// if the return value was not set
if Msg.Result = 0 then
inherited;
end;

procedure TDdhSizerControl.WmSize (var Msg: TWmSize);
var
R: TRect;
begin
R := BoundsRect;
InflateRect (R, -2, -2);
FControl.BoundsRect := R;
// setup data structures
FRectList [1] := Rect (0, 0, 5, 5);
FRectList [2] := Rect (Width div 2 - 3, 0,
Width div 2 + 2, 5);
FRectList [3] := Rect (Width - 5, 0, Width, 5);
FRectList [4] := Rect (Width - 5, Height div 2 - 3,
Width, Height div 2 + 2);
FRectList [5] := Rect (Width - 5, Height - 5,
Width, Height);
FRectList [6] := Rect (Width div 2 - 3, Height - 5,
Width div 2 + 2, Height);
FRectList [7] := Rect (0, Height - 5, 5, Height);
FRectList [8] := Rect (0, Height div 2 - 3,
5, Height div 2 + 2);
end;

procedure TDdhSizerControl.SizerControlExit (Sender: TObject);
begin
Free;
end;

procedure TDdhSizerControl.WmLButtonDown (var Msg: TWmLButtonDown);
begin
Perform (wm_SysCommand, sc_DragMove, 0);
end;

procedure TDdhSizerControl.WmMove (var Msg: TWmMove);
var
R: TRect;
begin
R := BoundsRect;
InflateRect (R, -2, -2);
FControl.Invalidate; // repaint entire surface
FControl.BoundsRect := R;
end;
procedure Register;
begin
RegisterComponents('Standard', [Tmshape1]);
end;

end.

up

程序太长啦……

最好把有什么不对的地方说一下。

很直观的，安装控件后WmNcHitTest(var Msg: TWmNcHitTest);好像没有响应。
不能改变大小。

控件是动态创建的

我怀疑WM_NCHITTEST对TGraphicControl类不起作用，而只对TWinControl起作用。

大富翁论坛显示格式功能表
eightball [8] ［８］
这些干扰了原码啊，　最好改为{8}

代码贴全了吗？ 我怎么没看到谁来建立TDdhSizerControl的实例呀？

这个是我改的源代码如下：是对于button的可以执行，
如果有一个可以运行期动态改变动态创建shape的大小的方法也可以
unit DDHSIZER;

interface

uses
Classes, Windows, Messages, Controls, StdCtrls;

const
sc_DragMove: Longint = $F012;

type
TDdhSizeButton = class (TButton)
public
procedure WmNcHitTest (var Msg: TWmNcHitTest);
message wm_NcHitTest;
end;

TDdhSizerControl = class (TCustomControl)
private
FControl: TControl;
FRectList: array [1..8] of TRect;
FPosList: array [1..8] of Integer;
public
constructor Create (AOwner: TComponent;
AControl: TControl);
procedure CreateParams (var Params: TCreateParams);
override;
procedure CreateHandle; override;
procedure WmNcHitTest (var Msg: TWmNcHitTest);
message wm_NcHitTest;
procedure WmSize (var Msg: TWmSize);
message wm_Size;
procedure WmLButtonDown (var Msg: TWmLButtonDown);
message wm_LButtonDown;
procedure WmMove (var Msg: TWmMove);
message wm_Move;
procedure Paint; override;
procedure SizerControlExit (Sender: TObject);
end;

procedure Register;

implementation

uses
Graphics;

// TDdhSizeButton methods

procedure TDdhSizeButton.WmNcHitTest(var Msg: TWmNcHitTest);
var
Pt: TPoint;
begin
Pt := Point (Msg.XPos, Msg.YPos);
Pt := ScreenToClient (Pt);
if (Pt.x < 5) and (pt.y < 5) then
Msg.Result := htTopLeft
else if (Pt.x > Width - 5) and (pt.y < 5) then
Msg.Result := htTopRight
else if (Pt.x > Width - 5) and (pt.y > Height - 5) then
Msg.Result := htBottomRight
else if (Pt.x < 5) and (pt.y > Height - 5) then
Msg.Result := htBottomLeft
else if (Pt.x < 5) then
Msg.Result := htLeft
else if (pt.y < 5) then
Msg.Result := htTop
else if (Pt.x > Width - 5) then
Msg.Result := htRight
else if (pt.y > Height - 5) then
Msg.Result := htBottom
else
inherited;
end;

// TDdhSizerControl methods

constructor TDdhSizerControl.Create (
AOwner: TComponent; AControl: TControl);
var
R: TRect;
begin
inherited Create (AOwner);
FControl := AControl;
// install the new handler
OnExit := SizerControlExit;
// set the size and position
R := FControl.BoundsRect;
InflateRect (R, 2, 2);
BoundsRect := R;
// set the parent
Parent := FControl.Parent;
// create the list of positions
FPosList [1] := htTopLeft;
FPosList [2] := htTop;
FPosList [3] := htTopRight;
FPosList [4] := htRight;
FPosList [5] := htBottomRight;
FPosList [6] := htBottom;
FPosList [7] := htBottomLeft;
FPosList [8] := htLeft;
end;

procedure TDdhSizerControl.CreateHandle;
begin
inherited CreateHandle;
SetFocus;
end;

procedure TDdhSizerControl.CreateParams (var Params: TCreateParams);
begin
inherited CreateParams(Params);
Params.ExStyle := Params.ExStyle +
ws_ex_Transparent;
end;

procedure TDdhSizerControl.Paint;
var
I: Integer;
begin
Canvas.Brush.Color := clBlack;
for I := 1 to 8 do
Canvas.Rectangle (FRectList .Left, FRectList .Top,
FRectList .Right, FRectList .Bottom);
end;

procedure TDdhSizerControl.WmNcHitTest(var Msg: TWmNcHitTest);
var
Pt: TPoint;
I: Integer;
begin
Pt := Point (Msg.XPos, Msg.YPos);
Pt := ScreenToClient (Pt);
Msg.Result := 0;
for I := 1 to 8 do
if PtInRect (FRectList , Pt) then
Msg.Result := FPosList ;
// if the return value was not set
if Msg.Result = 0 then
inherited;
end;

procedure TDdhSizerControl.WmSize (var Msg: TWmSize);
var
R: TRect;
begin
R := BoundsRect;
InflateRect (R, -2, -2);
FControl.BoundsRect := R;
// setup data structures
FRectList [1] := Rect (0, 0, 5, 5);
FRectList [2] := Rect (Width div 2 - 3, 0,
Width div 2 + 2, 5);
FRectList [3] := Rect (Width - 5, 0, Width, 5);
FRectList [4] := Rect (Width - 5, Height div 2 - 3,
Width, Height div 2 + 2);
FRectList [5] := Rect (Width - 5, Height - 5,
Width, Height);
FRectList [6] := Rect (Width div 2 - 3, Height - 5,
Width div 2 + 2, Height);
FRectList [7] := Rect (0, Height - 5, 5, Height);
FRectList [8] := Rect (0, Height div 2 - 3,
5, Height div 2 + 2);
end;

procedure TDdhSizerControl.SizerControlExit (Sender: TObject);
begin
Free;
end;

procedure TDdhSizerControl.WmLButtonDown (var Msg: TWmLButtonDown);
begin
Perform (wm_SysCommand, sc_DragMove, 0);
end;

procedure TDdhSizerControl.WmMove (var Msg: TWmMove);
var
R: TRect;
begin
R := BoundsRect;
InflateRect (R, -2, -2);
FControl.Invalidate; // repaint entire surface
FControl.BoundsRect := R;
end;

// components registration

procedure Register;
begin
RegisterComponents ('zdl', [TDdhSizeButton]);
RegisterNoIcon ([TDdhSizerControl]);
end;

end.

呵呵。 你没注意它注册的是两个控件吗？ 一个是button, 另一个是给你用于运行期生成后改变一个GraphicControl的大小的。
所以你的程序改动很简单：
1、去掉TmShape1里面的 procedure WmNcHitTest (var Msg: TWmNcHitTest);message wm_NcHitTest;定义。
2、将TDdhSizerControl和TmShape1的定义部分颠倒一下（先定义TDdhSizerControl，再定义TmShape1）。
3、在TmShape1的Private部分加一个变量：
FSizeCtrl: TDdhSizerControl;
4、在 TmShape2的Public部分加上以下一个定义：
procedure SetParent(AParent: TWinControl); override;

5、具体代码：
constructor TmShape1.SetParent(AParent: TWinControl);
begin
if Assigned(FSizeCtrl) then FreeAndNil(FSizeCtrl);
inherited;
if not (csDesigning in ComponentState) and Assigned(AParent) then
FSizeCtrl := TDdhSizerControl.Create(Self, Self);
end;

that's all.

谢谢，太疏忽了

帮忙看看1445571，按照eyes说的改掉之后可以改变了释放好像有问题

那就再加一个：
procedure Notification(AComponent: TComponent; Operation: TOperation); override;


procedure TmShape1.Notification(AComponent: TComponent; Operation: TOperation);
begin
if (AComponent=FSizeCtrl) and (Operation = opRemove) then
FSizeCtrl := nil;
Inherited;
end;