C++ Builder TDrawGrid控件基本用法，使用实例，一个例子（诚诚照片Demo（DrawGrid示例）v1.02）

//--------------------------------------------------------------------------- #include <vcl.h> #include <jpeg.hpp> #pragma hdrstop #include "Unit1.h" //--------------------------------------------------------------------------- #pragma package(smart_init) #pragma resource "*.dfm" TForm1 *Form1; //--------------------------------------------------------------------------- __fastcall TForm1::TForm1(TComponent* Owner) : TForm(Owner) { } //--------------------------------------------------------------------------- void __fastcall TForm1::DrawGrid1DrawCell(TObject *Sender, int ACol, int ARow, TRect &Rect, TGridDrawState State) { //获得DrawGrid的画布Canvas TCanvas *Canvas = DrawGrid1->Canvas; //照片文件名为cc (1).jpg到cc (9).jpg，根据单元格的ACol和ARow而定 AnsiString fileName="res\\cc ("+IntToStr(ARow*DrawGrid1->ColCount+ACol+1) +").jpg"; // ShowMessage(fileName); //照片不存在时显示提示信息并返回 if(!FileExists(fileName)) { Canvas->TextRect(Rect,Rect.Left,Rect.Top,fileName+" 不存在"); return; } //新建TJPEGImage对象jpgimg TJPEGImage *jpgimg; jpgimg=new TJPEGImage(); //读取照片 jpgimg->LoadFromFile(fileName); //向单元格区域绘制照片 if((float)jpgimg->Width/Rect.Width()==(float)jpgimg->Height/Rect.Height()) Canvas->StretchDraw(Rect, jpgimg); else if((float)jpgimg->Width/Rect.Width()<(float)jpgimg->Height/Rect.Height()) { int bW=jpgimg->Width*Rect.Height()/jpgimg->Height; int left=Rect.left+(Rect.Width()-bW)/2; TRect rect=TRect(left,Rect.top,left+bW,Rect.Bottom); Canvas->StretchDraw(rect,jpgimg); } else { int bH=jpgimg->Height*Rect.Width()/jpgimg->Width; int top=Rect.top+(Rect.Height()-bH)/2; TRect rect=TRect(Rect.Left,top,Rect.Right,top+bH); Canvas->StretchDraw(rect,jpgimg); } //删除jpgimg对象 delete jpgimg; } //--------------------------------------------------------------------------- void __fastcall TForm1::Button1Click(TObject *Sender) { ShowMessage("亲，给个赞吧！"); } //---------------------------------------------------------------------------