在 Android 中使用 HttpClient 和 HttpPost 以及 post 参数

json android java http-post httpclient

2022-09-01 07:19:31

我正在为一个Android应用程序编写代码，该应用程序应该获取数据，将其打包为Json并将其发布到Web服务器，而Web服务器又应该使用json进行响应。

使用GET请求工作正常，但由于某种原因使用POST，所有数据似乎都被剥离，服务器没有收到任何东西。

下面是代码片段：

HttpParams params = new BasicHttpParams();
HttpConnectionParams.setConnectionTimeout(params, 5000);
HttpConnectionParams.setSoTimeout(params, 5000);        
DefaultHttpClient httpClient = new DefaultHttpClient(params);
BasicCookieStore cookieStore = new BasicCookieStore();
httpClient.setCookieStore(cookieStore);

String uri = JSON_ADDRESS;
String result = "";
String username = "user";
String apikey = "something";
String contentType = "application/json";

JSONObject jsonObj = new JSONObject();

try {
    jsonObj.put("username", username);
    jsonObj.put("apikey", apikey);
} catch (JSONException e) {
    Log.e(TAG, "JSONException: " + e);
}

HttpPost httpPost = new HttpPost(uri);
List<NameValuePair> postParams = new ArrayList<NameValuePair>();
postParams.add(new BasicNameValuePair("json", jsonObj.toString()));
HttpGet httpGet = null;
try {
    UrlEncodedFormEntity entity = new UrlEncodedFormEntity(postParams);
    entity.setContentEncoding(HTTP.UTF_8);
    entity.setContentType("application/json");
    httpPost.setEntity(entity);

    httpPost.setHeader("Content-Type", contentType);
    httpPost.setHeader("Accept", contentType);
} catch (UnsupportedEncodingException e) {
    Log.e(TAG, "UnsupportedEncodingException: " + e);
}

try {
    HttpResponse httpResponse = httpClient.execute(httpPost);
    HttpEntity httpEntity = httpResponse.getEntity();

    if (httpEntity != null) {
        InputStream is = httpEntity.getContent();
        result = StringUtils.convertStreamToString(is);
        Log.i(TAG, "Result: " + result);
    }
} catch (ClientProtocolException e) {
    Log.e(TAG, "ClientProtocolException: " + e);
} catch (IOException e) {
    Log.e(TAG, "IOException: " + e);
}

return result;

我认为我已经遵循了有关如何创建参数并发布它们的一般准则，但显然不是。

在这一点上，任何帮助或指向我可以找到解决方案的指针都非常欢迎（在花了几个小时意识到没有发送任何帖子数据之后）。真正的服务器在Tomcat上运行Wicket，但我也在一个简单的PHP页面上进行了测试，没有任何区别。

答案 1

您实际上可以通过以下方式将其作为 JSON 发送：

// Build the JSON object to pass parameters
JSONObject jsonObj = new JSONObject();
jsonObj.put("username", username);
jsonObj.put("apikey", apikey);
// Create the POST object and add the parameters
HttpPost httpPost = new HttpPost(url);
StringEntity entity = new StringEntity(jsonObj.toString(), HTTP.UTF_8);
entity.setContentType("application/json");
httpPost.setEntity(entity);
HttpClient client = new DefaultHttpClient();
HttpResponse response = client.execute(httpPost);

答案 2

您是否尝试过在没有JSON对象的情况下执行此操作，并且刚刚传递了两个基本名称值对？此外，它可能与您的服务器设置有关

更新：这是我使用的一段代码：

InputStream is = null;
ArrayList<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();
    nameValuePairs.add(new BasicNameValuePair("lastupdate", lastupdate)); 

try {
        HttpClient httpclient = new DefaultHttpClient();
        HttpPost httppost = new HttpPost(connection);
        httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
        HttpResponse response = httpclient.execute(httppost);
        HttpEntity entity = response.getEntity();
        is = entity.getContent();
        Log.d("HTTP", "HTTP: OK");
    } catch (Exception e) {
        Log.e("HTTP", "Error in http connection " + e.toString());
    }