unit6.pas

delphi语言编写的简单图书馆管理系统页面适合初学者模仿练习！

unit Unit6;

interface

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

type
  TEditCourseForm = class(TForm)
    Label1: TLabel;
    Label2: TLabel;
    Label3: TLabel;
    Label4: TLabel;
    Label5: TLabel;
    Label6: TLabel;
    Button1: TButton;
    Button2: TButton;
    DBEdit1: TDBEdit;
    DataSource1: TDataSource;
    ADOQuery1: TADOQuery;
    DBEdit2: TDBEdit;
    DBEdit3: TDBEdit;
    DBEdit4: TDBEdit;
    DBEdit6: TDBEdit;
    ComboBox1: TComboBox;
    ADOQuery2: TADOQuery;
    ADOQuery3: TADOQuery;
    DBNavigator1: TDBNavigator;
    procedure Button2Click(Sender: TObject);
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  EditCourseForm: TEditCourseForm;
implementation

uses Unit1,Unit2, Unit5;

{$R *.dfm}

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

procedure TEditCourseForm.Button1Click(Sender: TObject);
begin
  if (dbedit1.Text='') or (dbedit2.Text='') or (dbedit3.Text='') or (dbedit4.Text='')
     or (dbedit6.Text='') then messagedlg(#10'请输入完整的课程信息',mtwarning,[mbOk],0)
  else begin
      ADOQuery2.close;
      ADOQuery2.SQL.Clear;
      ADOQuery2.SQL.Add('update course set cno=:Pcno,cname=:Pcname,credit=:Pcredit,class=:Pclass,teacher=:Pteacher,kind=:Pkind where cno=:ccno');
      ADOQuery2.Parameters.ParamByName('ccno').value:=ccno;
      ADOQuery2.Parameters.ParamByName('Pcno').value:=DBEdit1.text;
      ADOQuery2.Parameters.ParamByName('Pcname').value:=DBEdit3.text;
      ADOQuery2.Parameters.ParamByName('Pcredit').value:=DBEdit2.text;
      ADOQuery2.Parameters.ParamByName('Pclass').value:=DBEdit6.text;
      ADOQuery2.Parameters.ParamByName('Pteacher').value:=DBEdit4.text;
      ADOQuery2.Parameters.ParamByName('Pkind').value:=ComboBox1.Items[combobox1.itemindex];
                          //修改课程信息
if  ADOQuery2.Parameters.ParamByName('Pkind').value=''
  then  messagedlg(#10'请选择该课程性质!', mtwarning,[mbOk],0)
  //else begin
           // ADOQuery3.close;        //核对是否已存在相同的课号
           // ADOQuery3.SQL.Clear;
           // ADOQuery3.SQL.Add('select * from course where cno=:Pcno');
           // ADOQuery3.Parameters.ParamByName('Pcno').value:=dbedit1.text;
           // ADOQuery3.open;
         else if  not ADOQuery3.Eof then
               if (ccno=dbedit1.text) then
                      begin ADOQuery2.ExecSQL;
                            ManageForm.FormCreate(Sender);
                            ManageForm.EditEdit.Clear;
                            EditCourseForm.Close;
                      end
                  // else
                      // messagedlg(#10'该课号已存在,请核对输入!', mtwarning,[mbOk],0)
              else begin ADOQuery2.ExecSQL;
                         ManageForm.FormCreate(Sender);
                         ManageForm.EditEdit.Clear;
                         EditCourseForm.Close;
                 end
       end;
  end;
//end;

end.