public String delete(String id){
        HttpClient httpClient = new DefaultHttpClient();
        HttpDelete httpDelete = new HttpDelete(Url+"&id="+id);
        String backRes = "-1";
        try {
            HttpResponse httpResponse = httpClient.execute(httpDelete);
            int backCode = httpResponse.getStatusLine().getStatusCode();
            if(backCode == HttpStatus.SC_OK){
                String strBack = InputStreamUtils.inputStream2String(httpResponse.getEntity().getContent());
                JSONObject jsonBack = JSONObject.fromObject(strBack);
                backRes = jsonBack.getString("status");
                if(backRes.equals("0"))
                    return backRes;
                else
                    return "-1";
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
        return backRes;
    }