unit5.pas

应用ADO技术在Delphi中进行客户信息管理系统的开发。系统设计分为数据库设计和功能模块设计两部分。本系统的数据分为两部分：客户信息和系统用户信息。所以要设计两个表：Customers和Users

unit Unit5;

interface

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

type
  TFrmQuery = class(TForm)
    rdg: TRadioGroup;
    BtnReturn: TBitBtn;
    DSQryCondition: TDataSource;
    DSQruCu: TDataSource;
    ADOQryCondition: TADOQuery;
    ADOQryCu: TADOQuery;
    DBGrdQry: TDBGrid;
    dblcb: TDBLookupComboBox;
    procedure BtnReturnClick(Sender: TObject);
    procedure dblcbClick(Sender: TObject);
    procedure rdgClick(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  FrmQuery: TFrmQuery;

implementation

{$R *.dfm}

procedure TFrmQuery.rdgClick(Sender: TObject);
begin
  ADOQryCondition.Close;
  ADOQryCondition.SQL.Clear;
  case rdg.ItemIndex of
  0:
    begin
      ADOQryCondition.SQL.Add('select 客户编号 from customers');
      dblcb.KeyField:='客户编号';
      dblcb.ListField:='客户编号';
    end;
  1:
    begin
      ADOQryCondition.SQL.Add('select distinct 所在省份 from customers');
      dblcb.KeyField:='所在省份';
      dblcb.ListField:='所在省份';
    end;
  2:
    begin
      ADOQryCondition.SQL.Add('select distinct 所在城市 from customers');
      dblcb.KeyField:='所在城市';
      dblcb.ListField:='所在城市';
    end;
  3:
    begin
      ADOQryCondition.SQL.Add('select distinct 公司名称 from customers');
      dblcb.KeyField:='公司名称';
      dblcb.ListField:='公司名称';
    end;
  end;
  ADOQryCondition.Active:=true;
end;

procedure TFrmQuery.dblcbClick(Sender: TObject);
var
  SQLCmd:String;
begin
  ADOQryCu.Close;
  ADOQryCu.SQL.Clear;
  case rdg.ItemIndex of
  0: SQLCmd:='select * from Customers where 客户编号='+QuotedStr(dblcb.Text);
  1: SQLCmd:='select * from Customers where 所在省份='+QuotedStr(dblcb.Text);
  2: SQLCmd:='select * from Customers where 所在城市='+QuotedStr(dblcb.Text);
  3: SQLCmd:='select * from Customers where 公司名称='+QuotedStr(dblcb.Text);
  end;
  ADOQryCu.SQL.Add(SQLCmd);
  ADOQryCu.Active:=true;
end;

procedure TFrmQuery.BtnReturnClick(Sender: TObject);
begin
  close;
end;

end.