frmlogin.pas

这个是一个商务管理系统,包含了进销存,全国各地的定位系统

//创建用户登录窗体
unit FrmLogin;

interface

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

type
  TFormLogin = class(TForm)
    Label1: TLabel;
    Label2: TLabel;
    EditUserName: TEdit;
    EditPassword: TEdit;
    BtnOK: TButton;
    BtnCancel: TButton;
    DSUser: TADODataSet;
    procedure BtnOKClick(Sender: TObject);
  private
    { Private declarations }
  public
        CurUserName: string;
        CurUserType: integer;
    { Public declarations }
  end;

var
  FormLogin: TFormLogin;

implementation

{$R *.dfm}
//“确定”按钮的响应事件代码
procedure TFormLogin.BtnOKClick(Sender: TObject);
begin
        ModalResult := mrCancel;//默认返回模式是mrCancel
        CurUserName := '';//CurUserName变量和CurUserType变量保存当前登录用户的用户名和类型
        CurUserType := -1;//判断输入是否为空
        if ( not(EditPassWord.Text = '') and not(EditUserName.Text = '')) then
        begin
	//将TADODataSet控件的Active属性设置为False,准备新的一轮查询
                DSUser.Active := False;
		//设置TADODataSet控件的查询语句
                DSUser.CommandText := 'select type from SysUser where name = ''' + EditUserName.Text + ''' and password = ''' + EditPassWord.Text + '''';
               //开始查询
		DSUser.Active := True;
                //如果返回的数据集是空，则表示没有找到正确的用户记录
		if (DSUser.IsEmpty) then
                begin
                        Application.MessageBox('错误的用户名或密码！', '系统信息', MB_OK);
                end
                else
                begin
                        Application.MessageBox('登陆成功！', '系统信息', MB_OK);
                        //获取用户名和用户类型
			CurUserName := EditUserName.Text;
                        CurUserType := DSUser.FieldByName('type').AsInteger;
                        //返回模式为mrOK
			ModalResult := mrOK;
                end
        end;
end;

end.