如何实现控件的移动改变大小？

实现控件的移动，改变大小（DELPHI实现）

主要使用Perform方法
function Perform(Msg: Cardinal; WParam, LParam: Longint): Longint;

只要能够使用类似于win32API的函数SendMessage()，本方法同样可在其他环境里应用。

用Delphi实现
首先，建立一个应用程序，在一个窗体里加入一个Panel1，保存为main.pas；
然后，分别在Panel1的鼠标移动、鼠标按下事件里添加代码；
鼠标移动：控制光标的形状
procedure TForm1.Panel1MouseMove(Sender: TObject; Shift: TShiftState; X,
Y: Integer);
begin
if (x>=0)and(x<=3) then
begin
if (y>=0)and(y<=3) then Panel1.Cursor:=crSizeNWSE;
if (y>3)and(y<Panel1.Height-3) then Panel1.Cursor:=crSizeWE;
if (y>=Panel1.Height-3)and(y<=Panel1.Height) then Panel1.Cursor:=crSizeNESW;
end
else if (x>3)and(x<Panel1.Width-3) then
begin
if (y>=0)and(y<=3) then Panel1.Cursor:=crSizeNS;
if (y>3)and(y<Panel1.Height-3) then Panel1.Cursor:=crArrow;
if (y>=Panel1.Height-3)and(y<=Panel1.Width) then Panel1.Cursor:=crSizeNS;
end
else if (x>=Panel1.Width-3)and(x<=Panel1.Width) then
begin
if (y>=0)and(y<=3) then Panel1.Cursor:=crSizeNESW;
if (y>3)and(y<Panel1.Height-3) then Panel1.Cursor:=crSizeWE;
if (y>=Panel1.Height-3)and(y<=Panel1.Width) then Panel1.Cursor:=crSizeNWSE;
end;
end;

鼠标按下：控制Panel的大小或位置
procedure TForm1.Panel1MouseDown(Sender: TObject; Button: TMouseButton;
Shift: TShiftState; X, Y: Integer);
begin
ReleaseCapture;
if (x>=0)and(x<=3) then
begin
file://左上角方向改变大小
if (y>=0)and(y<=3) then Panel1.Perform(WM_SysCommand,$F004,0);
file://左侧
if (y>3)and(y<Panel1.Height-3) then Panel1.Perform(WM_SysCommand,$F001,0);
file://左下角
if (y>=Panel1.Height-3)and(y<=Panel1.Height) then Panel1.Perform(WM_SysCommand,$F007,0);
end
else if (x>3)and(x<Panel1.Width-3) then
begin
file://上侧
if (y>=0)and(y<=3) then Panel1.Perform(WM_SysCommand,$F003,0);
file://移动控件
if (y>3)and(y<Panel1.Height-3) then Panel1.Perform(WM_SysCommand,$F012,0);
file://下侧
if (y>=Panel1.Height-3)and(y<=Panel1.Width) then Panel1.Perform(WM_SysCommand,$F006,0);
end
else if (x>=Panel1.Width-3)and(x<=Panel1.Width) then
begin
file://右上角
if (y>=0)and(y<=3) then Panel1.Perform(WM_SysCommand,$F005,0);
file://右侧
if (y>3)and(y<Panel1.Height-3) then Panel1.Perform(WM_SysCommand,$F002,0);
file://右下角
if (y>=Panel1.Height-3)and(y<=Panel1.Width) then Panel1.Perform(WM_SysCommand,$F008,0);
end;
end;