classunit.pas

用Delphi做的一个学生数据库系统

unit classUnit;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, ImgList, ComCtrls, ExtCtrls, ToolWin, Grids, DBGrids, StdCtrls,
  DBActns, ActnList;

type
  Tclassform = class(TForm)
    ToolBar1: TToolBar;
    Panel1: TPanel;
    tb_first: TToolButton;
    tb_prior: TToolButton;
    tb_next: TToolButton;
    tb_last: TToolButton;
    tb_add: TToolButton;
    tb_uptate: TToolButton;
    tb_delete: TToolButton;
    tb_post: TToolButton;
    tb_cancel: TToolButton;
    tb_exit: TToolButton;
    ImageList1: TImageList;
    Label1: TLabel;
    Label2: TLabel;
    Label3: TLabel;
    Label4: TLabel;
    Label5: TLabel;
    Edit1: TEdit;
    Edit2: TEdit;
    Edit3: TEdit;
    Edit4: TEdit;
    Edit5: TEdit;
    DBGrid1: TDBGrid;
    ActionList1: TActionList;
    Action1: TAction;
    DataSetFirst1: TDataSetFirst;
    DataSetPrior1: TDataSetPrior;
    DataSetNext1: TDataSetNext;
    DataSetLast1: TDataSetLast;
    DataSetCancel1: TDataSetCancel;
    Edit6: TEdit;
    Label6: TLabel;
    procedure FormClose(Sender: TObject; var Action: TCloseAction);
    procedure tb_exitClick(Sender: TObject);
    procedure tb_addClick(Sender: TObject);
    procedure tb_postClick(Sender: TObject);
    procedure tb_deleteClick(Sender: TObject);
    procedure tb_uptateClick(Sender: TObject);
    procedure Edit1KeyPress(Sender: TObject; var Key: Char);
    procedure Edit5KeyPress(Sender: TObject; var Key: Char);
    procedure FormCreate(Sender: TObject);
    procedure Edit1Change(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  classform: Tclassform;
  flag2:boolean;
implementation

uses MainUnit, dm, login;

{$R *.dfm}

procedure Tclassform.FormClose(Sender: TObject; var Action: TCloseAction); //关闭子窗体
begin
flag2:=false;
action:=cafree;
mainform.tb_class.Down:=false;
end;

procedure Tclassform.tb_exitClick(Sender: TObject);  //关闭
begin
close;
end;

procedure Tclassform.tb_addClick(Sender: TObject);  //添加
begin
  edit1.Text:='';
  edit2.Text:='';
  edit3.Text:='';
  edit4.Text:='';
  edit5.Text:='';
  edit6.Text:='';
  edit1.SetFocus;
end;

procedure Tclassform.tb_postClick(Sender: TObject);  //保存
   var
 str:string;
begin
  dmform.ADOQuery_class.Close;
  dmform.ADOQuery_class.SQL.Clear;
  dmform.ADOQuery_class.SQL.Add('select * from class where 班级编号='+Trim(edit1.Text));
  dmform.ADOQuery_class.Open;
  if dmform.ADOQuery_class.RecordCount>=1 then
  begin
  dmform.ADOQuery_class.Close;
  dmform.ADOQuery_class.SQL.Clear;
  dmform.ADOQuery_class.SQL.Add('select * from class');
  dmform.ADOQuery_class.Open;
   application.MessageBox('该编号已经存在,请重新输入!','登录提示',mb_ok);
  end
    else
    begin
  str:='insert into class(班级编号,班级名称,所属院系,班主任,联系电话,班级描述) values (:a,:b,:c,:d,:e,:f)';
  dmform.ADOQuery_class.Close;
  dmform.ADOQuery_class.SQL.Clear;
  dmform.ADOQuery_class.SQL.Add(str);
  dmform.ADOQuery_class.Parameters[0].Value:=Trim(edit1.Text);
  dmform.ADOQuery_class.Parameters[1].Value:=Trim(edit2.Text);
  dmform.ADOQuery_class.Parameters[2].Value:=Trim(edit3.Text);
  dmform.ADOQuery_class.Parameters[3].Value:=Trim(edit4.Text);
  dmform.ADOQuery_class.Parameters[4].Value:=Trim(edit5.Text);
  dmform.ADOQuery_class.Parameters[5].Value:=Trim(edit6.Text);
  dmform.ADOQuery_class.ExecSQL;

  dmform.ADOQuery_class.Close;
  dmform.ADOQuery_class.SQL.Clear;
  dmform.ADOQuery_class.SQL.Add('select * from class');
  dmform.ADOQuery_class.Open;
  Application.MessageBox(' 保存成功!','提示',64)
  end;
end;

procedure Tclassform.tb_uptateClick(Sender: TObject);//修改
 var
 str:string;
begin
     try
str:='Update class set 班级名称=:b,所属院系=:c,班主任=:d,联系电话=:e,班级描述=:f where 班级编号=:a';
dmform.ADOQuery_class.Close;
dmform.ADOQuery_class.SQL.Clear;
dmform.ADOQuery_class.SQL.Add(str);
dmform.ADOQuery_class.Parameters.ParamByName('a').Value:=Trim(edit1.Text);
dmform.ADOQuery_class.Parameters.ParamByName('b').Value:=Trim(edit2.Text);
dmform.ADOQuery_class.Parameters.ParamByName('c').Value:=Trim(edit3.Text);
dmform.ADOQuery_class.Parameters.ParamByName('d').Value:=Trim(edit4.Text);
dmform.ADOQuery_class.Parameters.ParamByName('e').Value:=Trim(edit5.Text);
dmform.ADOQuery_class.Parameters.ParamByName('f').Value:=Trim(edit6.Text);
dmform.ADOQuery_class.ExecSQL;

 dmform.ADOQuery_class.Close;
 dmform.ADOQuery_class.SQL.Clear;
 dmform.ADOQuery_class.SQL.Add('select * from class');
 dmform.ADOQuery_class.Open;

 Application.MessageBox('修改成功!','提示',64)
       except
 Application.MessageBox('系统出错!','提示',64)
end;
   end;

   procedure Tclassform.tb_deleteClick(Sender: TObject);    //删除
begin
  if messagedlg('确定删除该记录吗？',mtConfirmation,[mbYes, mbNo],0)=mryes then
  begin
       dmform.ADOQuery_class.Delete;
  end;

end;
procedure Tclassform.Edit1KeyPress(Sender: TObject; var Key: Char);
var
m:boolean;                                                     //只允许输入数字
begin
    m:=(key<#8)or(key>#8)and(key<#48)or(key>#57);
    if m then
    key:=#0;
end;


procedure Tclassform.Edit5KeyPress(Sender: TObject; var Key: Char);
var
m:boolean;                                                     //只允许输入数字
begin
    m:=(key<#8)or(key>#8)and(key<#48)or(key>#57);
    if m then
    key:=#0;
end;

procedure Tclassform.FormCreate(Sender: TObject);
begin
flag2:=true;
DBGrid1.Columns.Items[0].Width:=50;    //设置列的宽度
DBGrid1.Columns.Items[1].Width:=80;
DBGrid1.Columns.Items[2].Width:=80;
DBGrid1.Columns.Items[3].Width:=80;
DBGrid1.Columns.Items[4].Width:=80;
DBGrid1.Columns.Items[5].Width:=250
end;

procedure Tclassform.Edit1Change(Sender: TObject);
begin
if edit1.Text='' then
    begin
     tb_post.Enabled:=false;
    end
    else
    begin
    tb_post.Enabled:=true;
    end;
end;

end.