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, DBTables, DB, Grids, DBGrids, StdCtrls;

type
  TForm1 = class(TForm)
    DataSource1: TDataSource;
    DBGrid1: TDBGrid;
    tblEmployee: TTable;
    Label1: TLabel;
    edtKey: TEdit;
    lblResult: TLabel;
    btnClose: TButton;
    GroupBox1: TGroupBox;
    btnGotoNearest: TButton;
    btnGotoKey: TButton;
    GroupBox2: TGroupBox;
    btnFindKey: TButton;
    btnFindNearest: TButton;
    GroupBox3: TGroupBox;
    btnLocate: TButton;
    cbxCaseInsensitive: TCheckBox;
    cbxPartialKey: TCheckBox;
    Label2: TLabel;
    Label3: TLabel;
    edtFirstName: TEdit;
    edtLastName: TEdit;
    procedure btnGotoKeyClick(Sender: TObject);
    procedure btnGotoNearestClick(Sender: TObject);
    procedure btnFindKeyClick(Sender: TObject);
    procedure btnFindNearestClick(Sender: TObject);
    procedure btnLocateClick(Sender: TObject);
    procedure btnCloseClick(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

//执行GotoKey查询
procedure TForm1.btnGotoKeyClick(Sender: TObject);
begin
  with tblEmployee do
  begin
    if IndexFieldNames = '' then
       IndexFieldNames := 'EmpNo';
    SetKey;
    FieldByName('EmpNo').AsString := edtKey.Text;
    if GotoKey then
       lblResult.Caption := '查找成功！'
    else
       lblResult.Caption := '查找失败';
  end;
end;

//执行GotoNearest查询
procedure TForm1.btnGotoNearestClick(Sender: TObject);
begin
  with tblEmployee do
  begin
    if IndexFieldNames = '' then
       IndexFieldNames := 'EmpNo';
    SetKey;
    FieldByName('EmpNo').AsString := edtKey.Text;
    GotoNearest;
  end;

  lblResult.Caption := '模糊查找完成！'
end;

//执行FindKey查询
procedure TForm1.btnFindKeyClick(Sender: TObject);
begin
  with tblEmployee do
  begin
    if IndexFieldNames = '' then
       IndexFieldNames := 'EmpNo';

    if FindKey([edtKey.Text]) then
       lblResult.Caption := '查找成功！'
    else
       lblResult.Caption := '查找失败';
  end;
end;

//执行FindNearest查询
procedure TForm1.btnFindNearestClick(Sender: TObject);
begin
  with tblEmployee do
  begin
    if IndexFieldNames = '' then
       IndexFieldNames := 'EmpNo';
    FindNearest([edtKey.Text]);
  end;

  lblResult.Caption := 'FindNearest模糊查找完成！'
end;

//执行Locate查询
procedure TForm1.btnLocateClick(Sender: TObject);
var lo:TLocateOptions ;
begin
  //设置是否大小写敏感
  if cbxCaseInsensitive.Checked then
    Include(lo, loCaseInsensitive)
  else
    Exclude(lo, loCaseInsensitive);

  //设置是否执行近似查询  
  if cbxPartialKey.Checked then
    Include(lo, loPartialKey)
  else
    Exclude(lo, loPartialKey);

  with tblEmployee do
  begin
    if Locate('FirstName;LastName', VarArrayof([edtFirstName.Text,
          edtLastName.Text]), lo) then
       lblResult.Caption := '查找成功！'
    else
       lblResult.Caption := '查找失败';
  end;

end;

procedure TForm1.btnCloseClick(Sender: TObject);
begin
  Close;
end;

end.