unit1.~pas

来自「Delphi函数参考大全的CD」· ~PAS 代码 · 共 53 行

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls;

type
  TForm1 = class(TForm)
    Button1: TButton;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.Button1Click(Sender: TObject);
var
  avg1,avg2: Integer;
begin
  With ADOQuery1 do
  begin
    Close;
    SQL.Clear;
    SQL.Add('select avg(语文) from 学生成绩表 where 班级 = :number');
    Parameters.ParamByName('number').Value := '三年一班';
    Open;
  end;
  avg1 := ADOQuery1.Fields[0].Value;
  With ADOQuery1 do
  begin
    Close;
    SQL.Clear;
    SQL.Add('select avg(语文) from 学生成绩表 where 班级 = :number');
    Parameters.ParamByName('number').Value := '三年二班';
    Open;
  end;
  avg2 := ADOQuery1.Fields[0].Value;
  ShowMessage('两个班级的最好成绩为 '+ FloatToStr(Max(avg1,avg2)));
end;


end.