Question

我正在基于android的JSON编写应用程序。我有Wamp Server。我的代码如下...... 在MainActivity中：

public class MainActivity extends AppCompatActivity {
EditText edUsername, edPassword;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    edUsername = (EditText) findViewById(R.id.editTextUsername);
    edPassword = (EditText) findViewById(R.id.editTextPassword);
}

public void onclickLogin(View v)
{
    String username = edUsername.getText().toString();
    String password = edPassword.getText().toString();
    String type = "login";

    BackgroundWorker backgroundWorker = new BackgroundWorker(this);
    backgroundWorker.execute(type, username, password);
}

和BackgroundWorker类如下：

public class BackgroundWorker extends AsyncTask<String, Void, String> {

Context context;
AlertDialog alertDialog;

BackgroundWorker(Context ctx)
{
    context = ctx;
}


@Override
protected String doInBackground(String... params) {

    String type = params[0];

    String login_url = "http://localhost/login.php";

    if(type.equals("login"))
    {
        try {

            Log.d("myapp1", "do 1");
            String user_name = params[1];
            String password = params[2];

            URL url = new URL(login_url);
            HttpURLConnection httpURLConnection = (HttpURLConnection) url.openConnection();
            httpURLConnection.setRequestMethod("POST");
            httpURLConnection.setDoOutput(true);
            httpURLConnection.setDoInput(true);

            Log.d("myapp1", "do 2");
            OutputStream outputStream = httpURLConnection.getOutputStream();
            Log.d("myapp1", "do 3");

            BufferedWriter bufferedWriter = new BufferedWriter(new OutputStreamWriter(outputStream, "UTF-8"));
            String post_data = URLEncoder.encode("user_name", "UTF-8") + "=" + URLEncoder.encode(user_name,"UTF-8") + "&"
                    + URLEncoder.encode("user_pass", "UTF-8") + "=" + URLEncoder.encode(password, "UTF-8");
            bufferedWriter.write(post_data);
            bufferedWriter.flush();
            bufferedWriter.close();
            outputStream.close();

            InputStream inputStream = httpURLConnection.getInputStream();
            BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(inputStream, "iso-8859-1"));
            String result = ""  ;
            String line = "";

            while ( (line = bufferedReader.readLine()) != null )
            {
                result += line;
            }

            bufferedReader.close();
            inputStream.close();
            httpURLConnection.disconnect();

            return result;

        } catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

    }

    return null;
}


@Override
protected void onPreExecute() {
    alertDialog = new AlertDialog.Builder(context).create();
    alertDialog.setTitle("Login Status");
}

@Override
protected void onPostExecute(String result) {
    alertDialog.setMessage(result);
    alertDialog.show();
}

@Override
protected void onProgressUpdate(Void... values) {
    super.onProgressUpdate(values);
}

}

在BackgroundWorker类中

，OutputStream方法不起作用...... 我在浏览器中测试了login.php并且它正常工作......但是OutputStream不起作用......请帮助...谢谢。

Answer 1

localhost指向同一设备，您正在运行代码。如果您在手机上运行代码，则会引用手机。

localhost被视为我自己。因此，如果您尝试从手机连接到localhost，它会尝试连接到手机（本身）。如果您尝试从PC连接，它将连接到 PC （到本身）。

要从手机连接到PC，您必须使用PC IP地址而不是localhost

OutputStream在android中无效

1 个答案: