main.pas

Delphi7数据库开发教程,包含该书21套实例

unit main;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, DBXpress, FMTBcd, DB, SqlExpr, ExtCtrls, DBCtrls, StdCtrls,
  Mask, Grids, DBGrids, DBClient, SimpleDS, Provider;

type
  TForm1 = class(TForm)
    SQLConnection1: TSQLConnection;
    SQLDataSet1: TSQLDataSet;
    DataSource1: TDataSource;
    DBEdit1: TDBEdit;
    DBNavigator1: TDBNavigator;
    Button1: TButton;
    SQLMonitor1: TSQLMonitor;
    SaveDialog1: TSaveDialog;
    Button2: TButton;
    SimpleDataSet1: TSimpleDataSet;
    DataSetProvider1: TDataSetProvider;
    ClientDataSet1: TClientDataSet;
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.Button1Click(Sender: TObject);
begin
  with SQLDataSet1 do
  begin
    CommandType := ctQuery;
    CommandText := 'INSERT INTO MyTable (FirstName, LastName, Age) ' +
                      'VALUES (:FirstName, :LastName, :Age)';
    Params[0].AsString := 'Anne';
    Params[1].AsString := 'Wang';
    Params[2].AsInteger := 22;
    ExecSQL;
  end;
end;

//保存TraceList中的跟踪记录
procedure TForm1.Button2Click(Sender: TObject);
var ret:integer;
    msg:String;
begin
  With SaveDialog1 do
  begin
    //如果执行了“保存文件”对话框
    if Execute then
    begin
      if FileExists(FileName) then
        //如果指定的文件存在就保存到指定的文件中
        SQLMonitor1.SaveToFile(FileName)
      else
      if FileExists(SQLMonitor1.FileName) then
      begin
        //如果指定的文件不存在就询问是否使用默认的文件名保存
        msg := '指定的文件不存在，是否使用默认的文件名' +
                #13 + PAnsiChar(SQLMonitor1.FileName)+ '保存跟踪记录？';
        ret := MessageBox(handle, PAnsiChar(msg), '保存跟踪记录',
                           MB_YESNO + MB_ICONQUESTION);
        if ret = IDYES then
           //根据TSQLMonitor组件的FileName属性保存跟踪记录
           SQLMonitor1.SaveToFile('');
      end
      else
        ShowMessage('指定的文件名不存在，保存跟踪记录失败');
    end
    else
      ShowMessage('用户取消了操作，不能保存记录');
  end;
end;

end.