BCB XE3在Image上绘制矩形

#endif
#ifndef ImportPictureH
#define ImportPictureH
//---------------------------------------------------------------------------
#include <System.Classes.hpp>
//在Image控件上画边长为20，间距为10的矩形
void __fastcall TForm1::Button1Click(TObject *Sender)
{
Image1->Canvas->Brush->Color=clRed;
//获得Image控件的高和宽，确定画矩形的范围
#pragma resource "*.dfm"
TForm1 *Form1;
bool Draw =false; //定义并初始化标志变量,布尔型变量Draw，是否允许绘制直线
int x_Old=10,y_Old=10,x_New,y_New; //矩形起点坐标，矩形终点坐标
int ImageHeight,ImageWidth;//Image控件的高和宽
}
x_Old+=30;
}
}
x_Old=10;
y_Old+=30;
}
}
//---------------------------------------------------------------------------
.h文件
//---------------------------------------------------------------------------
TMainMenu *MainMenu1;
TMenuItem *N1;
TMenuItem *N2;
TOpenPictureDialog *OpenPictureDialog1;
TPanel *Panel1;
TImage *Image1;
TButton *Button1;
void __fastcall N2Click(TObject *Sender);
bool &Handled)
{
//控件的宽高属性是以“像素”为单位的整型值，故通过舍入取整
Panel1->Width=Panel1->Width*1.1;
Panel1->Height=Panel1->Height*1.1;
}
//---------------------------------------------------------------------------
Panel1->Width=Panel1->Width*0.9;
Panel1->Height=Panel1->Height*0.9;
}
//---------------------------------------------------------------------------
bool &Handled);
void __fastcall Button1Click(TObject *Sender);
private: // User declarations
public: // User declarations
__fastcall TForm1(TComponent* Owner);
void __fastcall TForm1::FormMouseWheelDown(TObject *Sender, TShiftState Shift, TPoint &MousePos,
bool &Handled)
{
//控件的宽高属性是以“像素”为单位的整型值，故通过舍入取整
};
//---------------------------------------------------------------------------
extern PACKAGE TForm1 *Form1;
//---------------------------------------------------------------------------
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
: TForm(Owner)
{
}
//---------------------------------------------------------------------------
//导入图片
void __fastcall TForm1::N2Click(TObject *Sender)
{
if(OpenPictureDialog1->Execute())
{
Image1->Stretch =true;
Image1->Picture->LoadFromFile(OpenPictureDialog1->FileName);
{
if((x_Old<ImageWidth) &&(x_New<ImageWidth20;
y_New=y_Old+20;
Image1->Canvas->FrameRect(Rect(x_Old,y_Old,x_New,y_New));
void __fastcall FormMouseWheelDown(TObject *Sender, TShiftState Shift, TPoint &MousePos,
bool &Handled);
void __fastcall FormMouseWheelUp(TObject *Sender, TShiftState Shift, TPoint &MousePos,
#include <Vcl.ExtDlgs.hpp>
//---------------------------------------------------------------------------
class TForm1 : public TForm
{
__published: // IDE-managed Components
ImageHeight=Image1->Height;
ImageWidth=Image1->Width;
for(int i=0;i<ImageHeight/30;i++)
{
if((y_Old<ImageHeight)&&(y_New<ImageHeight))
{
for(int j=0;j<ImageWidth/30;j++)
#include <vcl.h>
#pragma hdrstop
#include "ImportPicture.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
实现绘制正方形20*20，要求每个正方形间距为10，正方形不能完整画在Image控件内，不绘制。
新建一个Form，添加一个Image控件，一个Panel控件，一个Button控件即可，OpenPictureDialog和MainMenu控件是用来打开图片的，与此功能无关。
.c文件
//---------------------------------------------------------------------------
#include <Vcl.Controls.hpp>
#include <Vcl.StdCtrls.hpp>
#include <Vcl.Forms.hpp>
#include <Vcl.ExtCtrls.hpp>
#include <Vcl.Menus.hpp>
#include <Vcl.Dialogs.hpp>
}
}
//---------------------------------------------------------------------------
void __fastcall TForm1::FormMouseWheelUp(TObject *Sender, TShiftState Shift, TPoint &MousePos,