uquery.~pas

delphi编写的图书管理系统,一般的管理系统

unit uquery;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, ExtCtrls, ComCtrls, StdCtrls, Buttons,DBTables;

type
  Tuqueryfrm = class(TForm)
    GroupBox1: TGroupBox;
    RadioButton1: TRadioButton;
    RadioButton2: TRadioButton;
    RadioButton3: TRadioButton;
    RadioButton4: TRadioButton;
    RadioButton5: TRadioButton;
    CheckBox1: TCheckBox;
    Label1: TLabel;
    Edit1: TEdit;
    BitBtn1: TBitBtn;
    ListView1: TListView;
    Label2: TLabel;
    BitBtn2: TBitBtn;
    BitBtn4: TBitBtn;
    Bevel1: TBevel;
    ComboBox1: TComboBox;
    Memo1: TMemo;
    Sdialog: TSaveDialog;
    procedure BitBtn4Click(Sender: TObject);
    procedure BitBtn1Click(Sender: TObject);
    procedure FormShow(Sender: TObject);
    procedure RadioButton4Click(Sender: TObject);
    procedure BitBtn2Click(Sender: TObject);
  private
  procedure is_check; //检查是否选择了“按图书类别”查询
  procedure setbooksql(var q:Tquery);//设置SQL语句
  procedure setbookparam(var q:Tquery;param:string);//设置参数化查询的参数
  procedure bookquery;//查询过程
    { Private declarations }
  public
    { Public declarations }

  end;

var
  uqueryfrm: Tuqueryfrm;

implementation
  uses main,global;
{$R *.dfm}

procedure Tuqueryfrm.is_check ;
begin
if radiobutton5.Checked then
begin
combobox1.Left :=edit1.Left ;
combobox1.Top :=edit1.Top ;
combobox1.Width :=edit1.Width ;
combobox1.Height :=edit1.Height ;
combobox1.Visible :=true;
edit1.Visible :=false;
end
else
if edit1.Visible=false then
begin
edit1.Left :=combobox1.Left ;
edit1.Top :=combobox1.Top ;
edit1.Width :=combobox1.Width ;
edit1.Height :=combobox1.Height ;
edit1.Visible :=true;
combobox1.Visible :=false;
end;
end;

procedure Tuqueryfrm.setbookparam(var q:Tquery;param:string);
begin
  if checkbox1.Checked then param:=param+'%';
  if radiobutton1.Checked then
  q.ParamByName('b_no').AsString :=param;
  if radiobutton2.Checked then
  q.ParamByName('b_name').AsString :=param;
  if radiobutton3.Checked then
  q.ParamByName('b_author').AsString :=param;
  if radiobutton4.Checked then
  q.ParamByName('b_publisher').AsString :=param;
  if radiobutton5.Checked then
  q.ParamByName('b_type').AsString :=param;
end;


procedure Tuqueryfrm.setbooksql(var q:Tquery);
begin
  q.SQL.Clear ;
  if radiobutton1.Checked then
  q.SQL.Add('select * from book_info where 图书编号 like :b_no');
  if radiobutton2.Checked then
  q.SQL.Add('select * from book_info where 书名 like :b_name');
  if radiobutton3.Checked then
  q.SQL.Add('select * from book_info where 作者 like :b_author');
  if radiobutton4.Checked then
  q.SQL.Add('select * from book_info where 出版社 like :b_publisher');
  if radiobutton5.Checked then
  q.SQL.Add('select * from book_info where 类别 like :b_type');
end;

procedure Tuqueryfrm.bookquery ;
var q:Tquery;
begin
  ListView1.Items.Clear;
  q := TQuery.Create(nil);
  q.DatabaseName :=DBName;
  SetBookSQL(q);
  if radiobutton5.Checked then setbookparam(q,combobox1.Items[combobox1.itemindex])
  else SetBookParam(q,edit1.Text);
  q.Open;
  while not q.Eof do
  begin
    with ListView1.Items.Add do
    begin
      Caption := q.FieldByName('图书编号').AsString;
      SubItems.Add(q.FieldByName('书名').AsString);
      SubItems.Add(q.FieldByName('作者').AsString);
      SubItems.Add(q.FieldByName('出版社').AsString);
      SubItems.Add(q.FieldByName('出版时间').AsString);
      SubItems.Add(q.FieldByName('书价').AsString);
      subitems.Add(q.fieldbyname('借阅次数').AsString);
      if isborrowed(caption) then subitems.Add('是') else subitems.Add('否');
    end;
    q.Next;
  end;
  label2.Caption:= '共'+IntToStr(q.RecordCount)+'本';
  q.Close;
  q.Free;
end;

procedure Tuqueryfrm.BitBtn4Click(Sender: TObject);
begin
close;
end;

procedure Tuqueryfrm.BitBtn1Click(Sender: TObject);
begin
  try
    Bookquery;
  except
    MessageDlg('查询失败',mtError,[mbok],0);
  end;
end;

procedure Tuqueryfrm.FormShow(Sender: TObject);
begin
listview1.Items.Clear ;
label2.Caption :='共0本';
if edit1.Visible then
begin
edit1.Clear ;
edit1.SetFocus ;
end;
end;

procedure Tuqueryfrm.RadioButton4Click(Sender: TObject);
begin
is_check;
end;

procedure Tuqueryfrm.BitBtn2Click(Sender: TObject);
var i,j:integer;
begin
if sdialog.Execute then
begin
  memo1.Lines.Clear ;
  for i:=0 to listview1.Items.Count-1 do
  with memo1.Lines do
  begin
  add(listview1.Columns[0].Caption +':'+listview1.Items[i].Caption);
  for j:=0 to listview1.Columns.Count-2 do
  add(listview1.Columns[j+1].Caption+':'+listview1.Items[i].SubItems.Strings[j]);
  add('----------------------');
  end;
memo1.Lines.SaveToFile(sdialog.FileName);
end;
end;

end.