unit4.~pas

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unit Unit4;

interface

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

type
  TSearchForm = class(TForm)
    Button1: TButton;
    Button2: TButton;
    Label1: TLabel;
    Label2: TLabel;
    Label3: TLabel;
    Label4: TLabel;
    Label5: TLabel;
    Label6: TLabel;
    DBText1: TDBText;
    DBText2: TDBText;
    DBText3: TDBText;
    DBText4: TDBText;
    DBText6: TDBText;
    ADOQuery1: TADOQuery;
    ADOQuery2: TADOQuery;
    ComboBox1: TComboBox;
    DataSource1: TDataSource;
    procedure Button2Click(Sender: TObject);
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  SearchForm: TSearchForm;

implementation

uses Unit1,Unit2;

{$R *.dfm}

procedure TSearchForm.Button2Click(Sender: TObject);
begin
  close;
end;

procedure TSearchForm.Button1Click(Sender: TObject);  //选课
begin
  ADOQuery2.close;
  ADOQuery2.SQL.Clear;
  ADOQuery2.SQL.Add('select * from sc where sno=:Psno and cno=:Pcno');
  ADOQuery2.Parameters.ParamByName('Psno').value:=MainForm.DBText3.Caption;
  ADOQuery2.Parameters.ParamByName('Pcno').value:=dbtext1.Caption;
  ADOQuery2.open;                                    //判断待选课程是否已选
  if not ADOQuery2.Eof then messagedlg(#10'您已经选过该课程,请核对课号!', mtwarning,[mbOk],0)
    else begin
              ADOQuery2.close;
              ADOQuery2.SQL.Clear;
              ADOQuery2.SQL.Add('insert into sc(sno,cno,kinder) values (:Psno,:Pcno,:Pkinder)');
              ADOQuery2.Parameters.ParamByName('Psno').value:=MainForm.DBText3.Caption;
              ADOQuery2.Parameters.ParamByName('Pcno').value:=dbtext1.Caption;
              ADOQuery2.Parameters.ParamByName('Pkinder').value:=ComboBox1.Items[combobox1.itemindex];
              ADOQuery2.ExecSQL;
                                                    //添加所选课程
              MainForm.FormCreate(Sender);
              MainForm.SearchEdit.Clear;
              
              SearchForm.Close;
         end;
end;

end.