請教一個組合查詢功能的代碼問題
procedure TForm2.BitBtn1Click(Sender: TObject);
var
str,str1,str2,str3,str4:string;
begin
str2:=trim(ComboBOX1.Text);
Str3:=comboBox2.Text;
str4:=trim(Edit1.Text);
str1:='''';
str:='select * from user_base where ' str2 '' str3 '' str1 str4 str1;
Adoquery1.Close;
Adoquery1.SQL.Clear;
Adoquery1.SQL.Add(str);
Adoquery1.Open;
close;
end;

問題：
當ComBobox3.text等於'and'或'or'時，再加上像上面一組的代碼，
//此時str2:=trim(combobx4.text),str3:=combobx5.text,str4:=tirm(Edit2.text);
當ComBobox6.text等於'and'或'or'時，再加上像上面一組的代碼，
//此時str2:=trim(combobx7.text),str3:=combobx8.text,str4:=tirm(Edit3.text);
這樣就構成了一個組合查詢，
請問要怎樣實現，謝謝！！！

編輯記錄

您已經會寫了呀! 只要注意一下判斷是否要加的該組條件的合法性 (合 SQL 語法) 就 OK.

下面是where子句寫法的一個範例
Unit1.dfm
[code delphi]
object Form1: TForm1
Left = 192
Top = 114
Width = 696
Height = 480
Caption = 'Form1'
Color = clBtnFace
Font.Charset = DEFAULT_CHARSET
Font.Color = clWindowText
Font.Height = -11
Font.Name = 'MS Sans Serif'
Font.Style = []
OldCreateOrder = False
OnClick = FormClick
PixelsPerInch = 96
TextHeight = 13
object ComboBox1: TComboBox
Left = 200
Top = 48
Width = 145
Height = 28
Font.Charset = DEFAULT_CHARSET
Font.Color = clWindowText
Font.Height = -16
Font.Name = 'MS Sans Serif'
Font.Style = []
ItemHeight = 20
ParentFont = False
TabOrder = 0
Text = 'ComboBox1'
end
object ComboBox2: TComboBox
Left = 360
Top = 48
Width = 57
Height = 28
Font.Charset = DEFAULT_CHARSET
Font.Color = clWindowText
Font.Height = -16
Font.Name = 'MS Sans Serif'
Font.Style = []
ItemHeight = 20
ItemIndex = 0
ParentFont = False
TabOrder = 1
Items.Strings = (

'='
'>'
'<')
end
object Memo1: TMemo
Left = 160
Top = 96
Width = 497
Height = 161
Font.Charset = DEFAULT_CHARSET
Font.Color = clWindowText
Font.Height = -16
Font.Name = 'MS Sans Serif'
Font.Style = []
ParentFont = False
TabOrder = 2
end
object RadioGroup1: TRadioGroup
Left = 24
Top = 32
Width = 121
Height = 105
Caption = 'RadioGroup1'
ItemIndex = 0
Items.Strings = (
'AND'
'OR')
TabOrder = 3
end
object Edit1: TEdit
Left = 432
Top = 48
Width = 209
Height = 28
Font.Charset = DEFAULT_CHARSET
Font.Color = clWindowText
Font.Height = -16
Font.Name = 'MS Sans Serif'
Font.Style = []
ParentFont = False
TabOrder = 4
Text = 'Edit1'
end
object BitBtn1: TBitBtn
Left = 160
Top = 272
Width = 75
Height = 25
Caption = 'BitBtn1'
TabOrder = 5
OnClick = BitBtn1Click
end
end
[/code]

Unit1.pas

[code delphi]
unit where_U;
interface
uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, StdCtrls, ExtCtrls, Buttons;
type
TForm1 = class(TForm)
ComboBox1: TComboBox;
ComboBox2: TComboBox;
Memo1: TMemo;
RadioGroup1: TRadioGroup;
Edit1: TEdit;
BitBtn1: TBitBtn;
procedure FormClick(Sender: TObject);
procedure BitBtn1Click(Sender: TObject);
private
{ Private declarations }
public
{ Public declarations }
end;
var
Form1: TForm1;
implementation
{$R *.dfm}
procedure TForm1.FormClick(Sender: TObject);
begin
Memo1.Lines.Clear
end;
procedure TForm1.BitBtn1Click(Sender: TObject);
begin
if Memo1.Lines.Count>0 then
begin
case RadioGroup1.ItemIndex of
0:
Memo1.Lines.Add('AND');
1:
Memo1.Lines.Add('OR')
end;
end;
Memo1.lines.add(format('(%s %s ''%s'')',[ComboBox1.Text,ComboBox2.Text,Edit1.Text ]))
end;
end.
[/code]
您可以自己延伸。
===================引 用 lzkevin 文 章===================
請教一個組合查詢功能的代碼問題
procedure TForm2.BitBtn1Click(Sender: TObject);
var
str,str1,str2,str3,str4:string;
begin
str2:=trim(ComboBOX1.Text);
Str3:=comboBox2.Text;
str4:=trim(Edit1.Text);
str1:='''';
str:='select * from user_base where ' str2 '' str3 '' str1 str4 str1;
Adoquery1.Close;
Adoquery1.SQL.Clear;
Adoquery1.SQL.Add(str);
Adoquery1.Open;
close;
end;

問題：
當ComBobox3.text等於'and'或'or'時，再加上像上面一組的代碼，
//此時str2:=trim(combobx4.text),str3:=combobx5.text,str4:=tirm(Edit2.text);
當ComBobox6.text等於'and'或'or'時，再加上像上面一組的代碼，
//此時str2:=trim(combobx7.text),str3:=combobx8.text,str4:=tirm(Edit3.text);
這樣就構成了一個組合查詢，
請問要怎樣實現，謝謝！！！

------
What do we live for if not to make life less difficult for each other?

 這是我現在還在用的土法, 很好用, 很容易懂, 沒有技巧, 唯一的缺點是組合條件越多, 程式碼越長, 參考看看



[code delphi]
procedure TForm_Rep532.btn_FilterClick(Sender: TObject);
var ft1, ft2, ft3, ft4, ft5, ft6, ft7: string;
fta: string;
ft6str: string;
morder, msql: string;
begin
SysUt.MsgDialog('銷貨資料調閱中....');
ft1:= '';
ft2:= '';
ft3:= '';
ft4:= '';
ft5:= '';
ft6:= '';
ft7:= '';
fta:= '';
// 貨倉(ismaster是為解決如果使用還原鍵時)
if ismaster then
if cbxDept.Text<>'' then ft1:= 'DEPTNO="' cbxDept.Text '"';
// 品牌
if cbxBrand.Text<>'' then ft2:= 'BRANDNO="' cbxBrand.Text '"';
// 銷貨日期
if (trim(eD1.Text)<>'') and (trim(eD2.Text)='') then
ft3:= 'FORMDATE>="' eD1.Text '"'
else if (trim(eD1.Text)='') and (trim(eD2.Text)<>'') then
ft3:= 'FORMDATE<="' eD2.Text '"'
else if (trim(eD1.Text)<>'') and (trim(eD2.Text)<>'') then
ft3:= '(FORMDATE>="' eD1.Text '") and '
'(FORMDATE<="' eD2.Text '")';
// 客戶編號
if (trim(eC1.Text)<>'') and (trim(eC2.Text)='') then
ft4:= 'VIPNO>="' eC1.Text '"'
else if (trim(eC1.Text)='') and (trim(eC2.Text)<>'') then
ft4:= 'VIPNO<="' eC2.Text '_"'
else if (trim(eC1.Text)<>'') and (trim(eC2.Text)<>'') then
ft4:= '(VIPNO>="' eC1.Text '") and '
'(VIPNO<="' eC2.Text '_")';
// 群組
if eG1.Text<>'' then ft5:= '(GROUPS like "' eG1.Text '%")';
if eG2.Text<>'' then begin
if ft5='' then ft5:= '(GROUPS like "' eG2.Text '%")'
else ft5:= ft5 ' or (GROUPS like "' eG2.Text '%")';
end;
if eG3.Text<>'' then begin
if ft5='' then ft5:= '(GROUPS like "' eG3.Text '%")'
else ft5:= ft5 ' or (GROUPS like "' eG3.Text '%")';
end;
if eG4.Text<>'' then begin
if ft5='' then ft5:= '(GROUPS like "' eG4.Text '%")'
else ft5:= ft5 ' or (GROUPS like "' eG4.Text '%")';
end;
if eG5.Text<>'' then begin
if ft5='' then ft5:= '(GROUPS like "' eG5.Text '%")'
else ft5:= ft5 ' or (GROUPS like "' eG5.Text '%")';
end;
// 計算憑單
ft6str:= '';
if eF1.Text<>'' then ft6str:= '"' eF1.Text '"';
if eF2.Text<>'' then begin
if ft6str='' then ft6str:= '"' eF2.Text '"'
else ft6str:= ft6str ',"' eF2.Text '"';
end;
if eF3.Text<>'' then begin
if ft6str='' then ft6str:= '"' eF3.Text '"'
else ft6str:= ft6str ',"' eF3.Text '"';
end;
if eF4.Text<>'' then begin
if ft6str='' then ft6str:= '"' eF4.Text '"'
else ft6str:= ft6str ',"' eF4.Text '"';
end;
if eF5.Text<>'' then begin
if ft6str='' then ft6str:= '"' eF5.Text '"'
else ft6str:= ft6str ',"' eF5.Text '"';
end;
if eF6.Text<>'' then begin
if ft6str='' then ft6str:= '"' eF6.Text '"'
else ft6str:= ft6str ',"' eF6.Text '"';
end;
if eF7.Text<>'' then begin
if ft6str='' then ft6str:= '"' eF7.Text '"'
else ft6str:= ft6str ',"' eF7.Text '"';
end;
if eF8.Text<>'' then begin
if ft6str='' then ft6str:= '"' eF8.Text '"'
else ft6str:= ft6str ',"' eF8.Text '"';
end;
if eF9.Text<>'' then begin
if ft6str='' then ft6str:= '"' eF9.Text '"'
else ft6str:= ft6str ',"' eF9.Text '"';
end;
if eF10.Text<>'' then begin
if ft6str='' then ft6str:= '"' eF10.Text '"'
else ft6str:= ft6str ',"' eF10.Text '"';
end;
if ft6str<>'' then ft6:= 'HEADNO in (' ft6str ')';
// 確認
if chbConf.Checked then ft7:= 'ISCONFIRM="Y"';
// 分析條件
if ft1 <> '' then fta:= '(' ft1 ')';
if ft2 <> '' then begin
if fta= '' then fta:= '(' ft2 ')'
else fta:= fta ' and (' ft2 ')';
end;
if ft3 <> '' then begin
if fta= '' then fta:= '(' ft3 ')'
else fta:= fta ' and (' ft3 ')';
end;
if ft4 <> '' then begin
if fta= '' then fta:= '(' ft4 ')'
else fta:= fta ' and (' ft4 ')';
end;
if ft5 <> '' then begin
if fta= '' then fta:= '(' ft5 ')'
else fta:= fta ' and (' ft5 ')';
end;
if ft6 <> '' then begin
if fta= '' then fta:= '(' ft6 ')'
else fta:= fta ' and (' ft6 ')';
end;
if ft7 <> '' then begin
if fta= '' then fta:= '(' ft7 ')'
else fta:= fta ' and (' ft7 ')';
end;
if fta<>'' then begin
Frame_Qdata.SQLfilter:= ' where ' fta ' and ' '('
Frame_Qdata.SQLfilterbefore ')';
end
else Frame_Qdata.SQLfilter:= ' where ' Frame_Qdata.SQLfilterbefore;
Frame_Qdata.SQLorder:= ' order by GROUPS, SHORTNAME, FORMDATE, DEPTNO, HEADNO, BODYNO';
Frame_Qdata.SQLstring:= Frame_Qdata.SQLfield
Frame_Qdata.SQLfilter
Frame_Qdata.SQLorder;
IBQ_D8000m.Close;
IBQ_D8000m.SQL.Text:= Frame_Qdata.SQLstring;
IBQ_D8000m.Open;
end;

[/code]

超感動....
非常感謝P.D版主與christie，
christie的方法很好，
但是個人覺得P.D版主的答案是我想要的，
所以分結給P.D版主，
同時再次感謝christie！

編輯記錄