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Android,从应用程序发送字符串到网络服务器

Android 来源:JonanK 6次浏览

我想做一个应用程序,我应该从应用程序发送数据到Web服务器。 到目前为止,我一直在搜索,但无法找到一个工作的例子,我发现一些使用asynctask哪些不起作用,所以任何帮助表示赞赏!Android,从应用程序发送字符串到网络服务器


===========解决方案如下:

试试下面的代码: –

import java.io.BufferedReader; 
import java.io.IOException; 
import java.io.InputStream; 
import java.io.InputStreamReader; 
import org.apache.http.HttpResponse; 
import org.apache.http.client.HttpClient; 
import org.apache.http.client.methods.HttpPost; 
import org.apache.http.entity.StringEntity; 
import org.apache.http.impl.client.DefaultHttpClient; 
import org.json.JSONObject; 
import android.net.ConnectivityManager; 
import android.net.NetworkInfo; 
import android.os.AsyncTask; 
import android.os.Bundle; 
import android.util.Log; 
import android.view.View; 
import android.view.View.OnClickListener; 
import android.widget.Button; 
import android.widget.EditText; 
import android.widget.TextView; 
import android.widget.Toast; 
import android.app.Activity; 
import com.hmkcode.android.vo.Person; 

public class MainActivity extends Activity implements OnClickListener { 

    TextView tvIsConnected; 
    EditText etName,etCountry,etTwitter; 
    Button btnPost; 

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

     // get reference to the views 
     tvIsConnected = (TextView) findViewById(R.id.tvIsConnected); 
     etName = (EditText) findViewById(R.id.etName); 
     etCountry = (EditText) findViewById(R.id.etCountry); 
     etTwitter = (EditText) findViewById(R.id.etTwitter); 
     btnPost = (Button) findViewById(R.id.btnPost); 

     // check if you are connected or not 
     if(isConnected()){ 
      tvIsConnected.setBackgroundColor(0xFF00CC00); 
      tvIsConnected.setText("You are conncted"); 
     } 
     else{ 
      tvIsConnected.setText("You are NOT conncted"); 
     } 

     // add click listener to Button "POST" 
     btnPost.setOnClickListener(this); 

    } 

    public static String POST(String url, Person person){ 
     InputStream inputStream = null; 
     String result = ""; 
     try { 

      // 1. create HttpClient 
      HttpClient httpclient = new DefaultHttpClient(); 

      // 2. make POST request to the given URL 
      HttpPost httpPost = new HttpPost(url); 

      String json = ""; 

      // 3. build jsonObject 
      JSONObject jsonObject = new JSONObject(); 
      jsonObject.accumulate("name", person.getName()); 
      jsonObject.accumulate("country", person.getCountry()); 
      jsonObject.accumulate("twitter", person.getTwitter()); 

      // 4. convert JSONObject to JSON to String 
      json = jsonObject.toString(); 

      // ** Alternative way to convert Person object to JSON string usin Jackson Lib 
      // ObjectMapper mapper = new ObjectMapper(); 
      // json = mapper.writeValueAsString(person); 

      // 5. set json to StringEntity 
      StringEntity se = new StringEntity(json); 

      // 6. set httpPost Entity 
      httpPost.setEntity(se); 

      // 7. Set some headers to inform server about the type of the content 
      httpPost.setHeader("Accept", "application/json"); 
      httpPost.setHeader("Content-type", "application/json"); 

      // 8. Execute POST request to the given URL 
      HttpResponse httpResponse = httpclient.execute(httpPost); 

      // 9. receive response as inputStream 
      inputStream = httpResponse.getEntity().getContent(); 

      // 10. convert inputstream to string 
      if(inputStream != null) 
       result = convertInputStreamToString(inputStream); 
      else 
       result = "Did not work!"; 

     } catch (Exception e) { 
      Log.d("InputStream", e.getLocalizedMessage()); 
     } 

     // 11. return result 
     return result; 
    } 

    public boolean isConnected(){ 
     ConnectivityManager connMgr = (ConnectivityManager) getSystemService(Activity.CONNECTIVITY_SERVICE); 
      NetworkInfo networkInfo = connMgr.getActiveNetworkInfo(); 
      if (networkInfo != null && networkInfo.isConnected()) 
       return true; 
      else 
       return false;  
    } 
    @Override 
    public void onClick(View view) { 

     switch(view.getId()){ 
      case R.id.btnPost: 
       if(!validate()) 
        Toast.makeText(getBaseContext(), "Enter some data!", Toast.LENGTH_LONG).show(); 
       // call AsynTask to perform network operation on separate thread 
       new HttpAsyncTask().execute("http://hmkcode.appspot.com/jsonservlet"); 
      break; 
     } 

    } 
    private class HttpAsyncTask extends AsyncTask<String, Void, String> { 
     @Override 
     protected String doInBackground(String... urls) { 

      person = new Person(); 
      person.setName(etName.getText().toString()); 
      person.setCountry(etCountry.getText().toString()); 
      person.setTwitter(etTwitter.getText().toString()); 

      return POST(urls[0],person); 
     } 
     // onPostExecute displays the results of the AsyncTask. 
     @Override 
     protected void onPostExecute(String result) { 
      Toast.makeText(getBaseContext(), "Data Sent!", Toast.LENGTH_LONG).show(); 
     } 
    } 

    private boolean validate(){ 
     if(etName.getText().toString().trim().equals("")) 
      return false; 
     else if(etCountry.getText().toString().trim().equals("")) 
      return false; 
     else if(etTwitter.getText().toString().trim().equals("")) 
      return false; 
     else 
      return true;  
    } 
    private static String convertInputStreamToString(InputStream inputStream) throws IOException{ 
     BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(inputStream)); 
     String line = ""; 
     String result = ""; 
     while((line = bufferedReader.readLine()) != null) 
      result += line; 

     inputStream.close(); 
     return result; 

    } 
} 

见下面的链接了解更多信息: –

http://hmkcode.com/android-send-json-data-to-server/

http://androidexample.com/How_To_Make_HTTP_POST_Request_To_Server_-_Android_Example/index.php?view=article_discription&aid=64&aaid=89


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