如何在 Android 中使用 WebService？

Question

我在asp.net中做了一个webservice，方法如下：

[WebMethod]
    public string getUser(string usr)
    {

        var json = "";
        var user = from result in dc.Persons
                   where result.username == usr
                   select result.password;

        JavaScriptSerializer jss = new JavaScriptSerializer();
       json = jss.Serialize(user);
        return json;
    }

返回指定用户的密码。

但是如何在我的 android 应用程序中使用此方法？

假设我想获取用户的密码：Rambo ？

Answer 1

为此，我们通常使用 REST Web 服务和 GET/Post。为此使用 Volley，网络上有许多如何使用它的示例。这是我最喜欢的： Tutorial for Volley

Example.URL: http://DomainOrIpAdress/Accounts/getPassword?user=Rambo <- this is GET Request OR
             http://DomainOrIpAdress/Accounts/getPassword <- this is POST Request

本教程展示了如何获取您返回 json 的响应，然后您必须使用 JsonObjectRequest。好吧，这就是我多次这样做的方式。

Answer 2

在Android中，你需要像这样使用AnyncTask在后台运行httpget调用。

private final String API_URL = "www.example.com/api/{YourControllerName}/getUser?usr="
private class HttpGetter extends AsyncTask<URL, Void, Void> {

                @Override
                protected Void doInBackground(arg... args) {
                        // TODO Auto-generated method stub
                        StringBuilder builder = new StringBuilder();
                        HttpClient client = new DefaultHttpClient();
                        HttpGet httpGet = new HttpGet(API_URL + arg[0]);

                        try {
                                HttpResponse response = client.execute(httpGet);
                                StatusLine statusLine = response.getStatusLine();
                                int statusCode = statusLine.getStatusCode();
                                if (statusCode == 200) {
                                        HttpEntity entity = response.getEntity();
                                        InputStream content = entity.getContent();
                                        BufferedReader reader = new BufferedReader(
                                                        new InputStreamReader(content));
                                        String line;
                                        while ((line = reader.readLine()) != null) {
                                                builder.append(line);
                                        }
                                        Log.v("Getter", "Your data: " + builder.toString()); //response data
                                } else {
                                        Log.e("Getter", "Failed");
                                }
                        } catch (ClientProtocolException e) {
                                e.printStackTrace();
                        } catch (IOException e) {
                                e.printStackTrace();
                        }

                        return null;
                }
    }

HttpGetter get = new HttpGetter();
get.execute("Rambo");