unit frmxxcx;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, DB, DBTables, StdCtrls, Mask, DBCtrls, Buttons, ExtCtrls, Grids,
  DBGrids;

type
  Tfrmcx = class(TForm)
    Table1: TTable;
    ComboBox1: TComboBox;
    Button1: TButton;
    DBNavigator1: TDBNavigator;
    BitBtn1: TBitBtn;
    dsstudent: TDataSource;
    Qrystudent: TQuery;
    Edit1: TEdit;
    DBGrid1: TDBGrid;
    Label1: TLabel;
    Label2: TLabel;

    procedure Button1Click(Sender: TObject);
    procedure ComboBox1Change(Sender: TObject);
    procedure FormActivate(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  frmcx: Tfrmcx;

implementation
 uses dm3;
{$R *.dfm}

{procedure Tfrmcx.FormActivate(Sender: TObject);
begin
table1.First;
//table2.First;
while not table1.Eof do
begin
//如果組合框中沒有則添加
if combobox1.Items.IndexOf(table1.Fieldbyname('classno').Value )<0 then
combobox1.Items.Add(table1.fieldbyname('classno').Value);
table1.Next;
end;
combobox1.Text:=combobox1.Items[2];
end;}

procedure Tfrmcx.Button1Click(Sender: TObject);
var sname:string;
classno:integer;
begin
  if combobox1.Text='學號'then
     begin
     classno:=strtoint(Edit1.text);
     table1.Open;
     if table1.Locate('學號',classno,[])then
      //如果存在該學號
        begin
        qrystudent.Close;
        qrystudent.ParamByName('學號').Value:=classno;
        qrystudent.Prepare;
        qrystudent.Open;  //如果數據表中存在該班名，則查詢
        end
        else
        showmessage('沒有查找到相關信息!'  );
        end
    else
      begin
      sname:=Edit1.text;
      table1.Open;
      if table1.Locate('姓名',sname,[])then
       //如果存在該姓名
        begin
        qrystudent.Close;
        qrystudent.ParamByName('姓名').Value:=sname;
        qrystudent.Prepare;
        qrystudent.Open;  //如果數據表中存在該學生名，則查詢
        end
        else
        showmessage('沒有查找到相關信息!'  );
        
      end ;
end;

procedure Tfrmcx.ComboBox1Change(Sender: TObject);
begin
  if  combobox1.Text='學號' then
  begin

      Qrystudent.Close;
      Qrystudent.sql.Clear;
      Qrystudent.sql.Add('select * from student.db where 學號=:學號');
   end
   else
   begin
      Qrystudent.Close;
      Qrystudent.sql.Clear;
      Qrystudent.sql.Add('select * from student.db where 姓名=:姓名');
   end;
   edit1.SetFocus;   
end;

procedure Tfrmcx.FormActivate(Sender: TObject);
begin
edit1.SetFocus;
end;

end.