procedure TForm4.Button1Click(Sender: TObject);
var usname,olduspwd,newuspwd,qrpwd,sqlstr:string;
begin
usname:=trim(Form1.Edit1.Text);
olduspwd:=trim(old_Edit1.Text);
newuspwd:=trim(new1_Edit2.Text);
   if length(newuspwd)<3 then
   begin
   Showmessage('密碼由3-20個字符或數字組成！');
   exit;
   end;
qrpwd:=trim(new2_Edit3.Text);
   if(newuspwd<>qrpwd) then
   begin
   Showmessage('確認密碼不正確！');
   exit;
   end;
sqlstr:='select from pwd where (usname=''''+usname+'''')and (uspwd=''''+olduspwd+'''')';
begin
Form1.ADOquery1.Close ;
   Form1.ADOQuery1.SQL.Clear ;
   Form1.ADOQuery1.SQL.Add(sqlstr);
   Form1.ADOQuery1.Open;
   if Form1.ADOQuery1.recordcount<1 then
   begin
     Showmessage('原密碼錯誤，你不能修改--'+usname+'--用戶的密碼！');
     exit;
   end;
   sqlstr:='update pwd set uspwd='''+newuspwd+'''where(usname='''+usname+''')';
   Form1.ADOQuery1.SQL.Clear;
   Form1.ADOQuery1.SQL.Add(sqlstr);



Showmessage('密碼修改成功！');
 Close;
end;
end;
end.