child_chart1.pas

一个桌面数据库应用的源码,适合初学数据库编程的新手.

unit Child_Chart1;

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  Db, DBTables, TeEngine, Series, TeeProcs, Chart, ExtCtrls;

type
  Tfrm_Chart1 = class(TForm)
    Panel1: TPanel;
    Chart1: TChart;
    Series1: TBarSeries;
    Table1: TTable;
    Table2: TTable;
    procedure FormClose(Sender: TObject; var Action: TCloseAction);
    procedure FormCreate(Sender: TObject);
    procedure FormActivate(Sender: TObject);
    procedure FormShow(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  frm_Chart1: Tfrm_Chart1;

implementation

uses Main;

{$R *.DFM}

procedure Tfrm_Chart1.FormClose(Sender: TObject; var Action: TCloseAction);
begin
  with Mainform do
  begin
    if MDIChildCount=1 then
      StatusBar.Panels[1].Text:='';
  end;
  Table1.Close;
  Table2.Close;
  Action:=caFree;
end;

procedure Tfrm_Chart1.FormCreate(Sender: TObject);
begin
  Height:=Constraints.MinHeight;
  Width:=Constraints.MinWidth;
  Panel1.Align:=alClient;
  Chart1.Align:=alClient;
  Table1.DatabaseName:=MainForm.GetExePath+'mdb';
  Table1.TableName:='Lab.DB';
  Table1.Open;
  Table2.DatabaseName:=MainForm.GetExePath+'mdb';
  Table2.TableName:='Type.DB';
  Table2.Open;
end;

procedure Tfrm_Chart1.FormActivate(Sender: TObject);
begin
  MainForm.StatusBar.Panels[1].Text:='仪器分类统计图表';
end;

procedure Tfrm_Chart1.FormShow(Sender: TObject);
var
  i:integer;
  data_sum:array[1..127] of integer;
  Data_Name:array[1..127] of String;
begin
  for i:=1 to Table2.RecordCount do
    data_sum[i]:=0;
  Table1.First;
  while not Table1.Eof do
  begin
    Table2.First;
    while not Table2.Eof do
    begin
      if Table1.FieldByName('分类').AsString=Table2.Fields[0].AsString then
          data_sum[Table2.RecNo]:=data_sum[Table2.RecNo]+1;
      data_name[Table2.RecNo]:=Table2.Fields[1].AsString;
      Table2.Next;
    end;
    Table1.Next;
  end;
  for i:=1 to Table2.RecordCount do
    Series1.Add(data_sum[i],Data_Name[i],clTeeColor);
end;

end.