unit3.~pas

用户可选择不同权限进入系统。当以管理员权限进入系统时

unit Unit3;

interface

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

type
  TForm3 = class(TForm)
    Label1: TLabel;
    Edit1: TEdit;
    Label2: TLabel;
    Edit2: TEdit;
    Button1: TButton;
    ADOQuery1: TADOQuery;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form3: TForm3;

implementation

uses Unit1;

{$R *.dfm}

procedure TForm3.Button1Click(Sender: TObject);
var
temp:string;
begin
if edit1.text='' then
begin
MessageBox(0,'请输入原密码','警告',MB_ICONEXCLAMATION);
end
else if edit2.text='' then
begin
MessageBox(0,'新密码不能设置为空','警告',MB_ICONEXCLAMATION);
end
else
begin
ADOQuery1.Close;
ADOQuery1.SQL.Clear;
ADOQuery1.SQL.Text:='select 用户ID from login2 where 用户密码='+edit1.text+'and 用户ID='+form1.edit1.text+'';
ADOQuery1.open;
temp:=ADOQuery1.FieldByName('用户ID').AsString;
if temp='' then
begin
MessageBox(0,'原密码输入错误','警告',MB_ICONEXCLAMATION);
edit1.text:='';
edit2.text:='';
end
else
begin
ADOQuery1.SQL.add('update login2 set 用户密码='+Edit2.Text+'where 用户ID='+temp+'');
ADOQuery1.ExecSQL;
MessageBox(0,'密码修改成功','警告',MB_ICONEXCLAMATION);
edit1.text:='';
edit2.text:='';
end
end
end;

end.