在新版本的Android中，你必须把所有的web I/O请求放到一个新的线程中。AsyncTask最适合小请求。

方法将数据作为HTTP请求发布，

public static InputStream callPostService(String Url,
        List<NameValuePair> data) {
    HttpClient httpclient = new DefaultHttpClient();
    HttpPost httppost = new HttpPost(Url);
    try {
        httppost.setEntity(new UrlEncodedFormEntity(data));
        HttpResponse response = httpclient.execute(httppost);
        HttpEntity entity = response.getEntity();
        return entity.getContent();
    } catch (ClientProtocolException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }
    return null;
}

你可以使用URLConnection setDoOutput(true)， getOutputStream()(用于发送数据)，和getInputStream()(用于接收)。Sun在这方面有一个例子。

在新版本的Android中，你必须把所有的web I/O请求放到一个新的线程中。AsyncTask最适合小请求。

我在这个视频教程中找到了这个有用的例子。

连接器类:

package com.tutorials.hp.mysqlinsert;
import java.io.IOException;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
/**
 * Created by Oclemmy on 3/31/2016 for ProgrammingWizards Channel.
 */
public class Connector {
    /*
 1.SHALL HELP US ESTABLISH A CONNECTION TO THE NETWORK
 2. WE ARE MAKING A POST REQUEST
  */
    public static HttpURLConnection connect(String urlAddress) {
        try
        {
            URL url=new URL(urlAddress);
            HttpURLConnection con= (HttpURLConnection) url.openConnection();
            //SET PROPERTIES
            con.setRequestMethod("POST");
            con.setConnectTimeout(20000);
            con.setReadTimeout(20000);
            con.setDoInput(true);
            con.setDoOutput(true);
            //RETURN
            return con;
        } catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return null;
    }
 }

DataPackager经济舱:

package com.tutorials.hp.mysqlinsert;
import org.json.JSONException;
import org.json.JSONObject;
import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;
import java.util.Iterator;
/**
 * Created by Oclemmy on 3/31/2016 for ProgrammingWizards Channel.
 * 1.BASICALLY PACKS DATA WE WANNA SEND
 */
public class DataPackager {
    String name,position,team;
    /*
    SECTION 1.RECEIVE ALL DATA WE WANNA SEND
     */
    public DataPackager(String name, String position, String team) {
        this.name = name;
        this.position = position;
        this.team = team;
    }
    /*
   SECTION 2
   1.PACK THEM INTO A JSON OBJECT
   2. READ ALL THIS DATA AND ENCODE IT INTO A FROMAT THAT CAN BE SENT VIA NETWORK
    */
    public String packData()
    {
        JSONObject jo=new JSONObject();
        StringBuffer packedData=new StringBuffer();
        try
        {
            jo.put("Name",name);
            jo.put("Position",position);
            jo.put("Team",team);
            Boolean firstValue=true;
            Iterator it=jo.keys();
            do {
                String key=it.next().toString();
                String value=jo.get(key).toString();
                if(firstValue)
                {
                    firstValue=false;
                }else
                {
                    packedData.append("&");
                }
                packedData.append(URLEncoder.encode(key,"UTF-8"));
                packedData.append("=");
                packedData.append(URLEncoder.encode(value,"UTF-8"));
            }while (it.hasNext());
            return packedData.toString();
        } catch (JSONException e) {
            e.printStackTrace();
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        return null;
        }
}

电视台经济舱:

package com.tutorials.hp.mysqlinsert;
import android.app.ProgressDialog;
import android.content.Context;
import android.os.AsyncTask;
import android.widget.EditText;
import android.widget.Toast;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.net.HttpURLConnection;
/**
 * Created by Oclemmy on 3/31/2016 for ProgrammingWizards Channel and Camposha.com.
 * 1.SEND DATA FROM EDITTEXT OVER THE NETWORK
 * 2.DO IT IN BACKGROUND THREAD
 * 3.READ RESPONSE FROM A SERVER
 */
public class Sender extends AsyncTask<Void,Void,String> {
    Context c;
    String urlAddress;
    EditText nameTxt,posTxt,teamTxt;
    String name,pos,team;
    ProgressDialog pd;
    /*
            1.OUR CONSTRUCTOR
    2.RECEIVE CONTEXT,URL ADDRESS AND EDITTEXTS FROM OUR MAINACTIVITY
    */
    public Sender(Context c, String urlAddress,EditText...editTexts) {
        this.c = c;
        this.urlAddress = urlAddress;
        //INPUT EDITTEXTS
        this.nameTxt=editTexts[0];
        this.posTxt=editTexts[1];
        this.teamTxt=editTexts[2];
        //GET TEXTS FROM EDITEXTS
        name=nameTxt.getText().toString();
        pos=posTxt.getText().toString();
        team=teamTxt.getText().toString();
    }
    /*
   1.SHOW PROGRESS DIALOG WHILE DOWNLOADING DATA
    */
    @Override
    protected void onPreExecute() {
        super.onPreExecute();
        pd=new ProgressDialog(c);
        pd.setTitle("Send");
        pd.setMessage("Sending..Please wait");
        pd.show();
    }
    /*
    1.WHERE WE SEND DATA TO NETWORK
    2.RETURNS FOR US A STRING
     */
    @Override
    protected String doInBackground(Void... params) {
        return this.send();
    }
    /*
  1. CALLED WHEN JOB IS OVER
  2. WE DISMISS OUR PD
  3.RECEIVE A STRING FROM DOINBACKGROUND
   */
    @Override
    protected void onPostExecute(String response) {
        super.onPostExecute(response);
        pd.dismiss();
        if(response != null)
        {
            //SUCCESS
            Toast.makeText(c,response,Toast.LENGTH_LONG).show();
            nameTxt.setText("");
            posTxt.setText("");
            teamTxt.setText("");
        }else
        {
            //NO SUCCESS
            Toast.makeText(c,"Unsuccessful "+response,Toast.LENGTH_LONG).show();
        }
    }
/*
SEND DATA OVER THE NETWORK
RECEIVE AND RETURN A RESPONSE
 */
    private String send()
    {
        //CONNECT
        HttpURLConnection con=Connector.connect(urlAddress);
        if(con==null)
        {
            return null;
        }
        try
        {
            OutputStream os=con.getOutputStream();
            //WRITE
            BufferedWriter bw=new BufferedWriter(new OutputStreamWriter(os,"UTF-8"));
            bw.write(new DataPackager(name,pos,team).packData());
            bw.flush();
            //RELEASE RES
            bw.close();
            os.close();
            //HAS IT BEEN SUCCESSFUL?
            int responseCode=con.getResponseCode();
            if(responseCode==con.HTTP_OK)
            {
                //GET EXACT RESPONSE
                BufferedReader br=new BufferedReader(new InputStreamReader(con.getInputStream()));
                StringBuffer response=new StringBuffer();
                String line;
                //READ LINE BY LINE
                while ((line=br.readLine()) != null)
                {
                    response.append(line);
                }
                //RELEASE RES
                br.close();
                return response.toString();
            }else
            {
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
        return null;
    }
}

MainActivity:

package com.tutorials.hp.mysqlinsert;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
/*
1.OUR LAUNCHER ACTIVITY
2.INITIALIZE SOME UI STUFF
3.WE START SENDER ON BUTTON CLICK
 */
public class MainActivity extends AppCompatActivity {
    String urlAddress="http://10.0.2.2/android/poster.php";
    EditText nameTxt,posTxt,teamTxt;
    Button saveBtn;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);
        //INITIALIZE UI FIELDS
        nameTxt= (EditText) findViewById(R.id.nameEditTxt);
        posTxt= (EditText) findViewById(R.id.posEditTxt);
        teamTxt= (EditText) findViewById(R.id.teamEditTxt);
        saveBtn= (Button) findViewById(R.id.saveBtn);
        saveBtn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                //START ASYNC TASK
                Sender s=new Sender(MainActivity.this,urlAddress,nameTxt,posTxt,teamTxt);
                s.execute();
            }
        });
    }
}

ContentMain.xml:

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    app:layout_behavior="@string/appbar_scrolling_view_behavior"
    tools:context="com.tutorials.hp.mysqlinsert.MainActivity"
    tools:showIn="@layout/activity_main">
    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello World!" />
    <LinearLayout
        android:layout_width="fill_parent"
        android:layout_height="match_parent"
        android:layout_marginTop="?attr/actionBarSize"
        android:orientation="vertical"
        android:paddingLeft="15dp"
        android:paddingRight="15dp"
        android:paddingTop="50dp">
        <android.support.design.widget.TextInputLayout
            android:id="@+id/nameLayout"
            android:layout_width="match_parent"
            android:layout_height="wrap_content">
            <EditText
                android:id="@+id/nameEditTxt"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:singleLine="true"
                android:hint= "Name" />
        </android.support.design.widget.TextInputLayout>
        <android.support.design.widget.TextInputLayout
            android:id="@+id/teamLayout"
            android:layout_width="match_parent"
            android:layout_height="wrap_content">
            <EditText
                android:id="@+id/teamEditTxt"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:hint="Description" />
        </android.support.design.widget.TextInputLayout>
        <android.support.design.widget.TextInputLayout
            android:id="@+id/posLayout"
            android:layout_width="match_parent"
            android:layout_height="wrap_content">
            <EditText
                android:id="@+id/posEditTxt"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:hint="Position" />
            <!--android:inputType="textPassword"-->
        </android.support.design.widget.TextInputLayout>
        <Button android:id="@+id/saveBtn"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:text="Save"
            android:clickable="true"
            android:background="@color/colorAccent"
            android:layout_marginTop="40dp"
            android:textColor="@android:color/white"/>
    </LinearLayout>
</RelativeLayout>

通过这种方式，我们可以用http post方法发送数据并获得结果

     public class MyHttpPostProjectActivity extends Activity implements OnClickListener {

    private EditText usernameEditText;
    private EditText passwordEditText;
    private Button sendPostReqButton;
    private Button clearButton;

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.login);

        usernameEditText = (EditText) findViewById(R.id.login_username_editText);
        passwordEditText = (EditText) findViewById(R.id.login_password_editText);

        sendPostReqButton = (Button) findViewById(R.id.login_sendPostReq_button);
        sendPostReqButton.setOnClickListener(this);

        clearButton = (Button) findViewById(R.id.login_clear_button);
        clearButton.setOnClickListener(this);        
    }

    @Override
    public void onClick(View v) {

        if(v.getId() == R.id.login_clear_button){
            usernameEditText.setText("");
            passwordEditText.setText("");
            passwordEditText.setCursorVisible(false);
            passwordEditText.setFocusable(false);
            usernameEditText.setCursorVisible(true);
            passwordEditText.setFocusable(true);
        }else if(v.getId() == R.id.login_sendPostReq_button){
            String givenUsername = usernameEditText.getEditableText().toString();
            String givenPassword = passwordEditText.getEditableText().toString();

            System.out.println("Given username :" + givenUsername + " Given password :" + givenPassword);

            sendPostRequest(givenUsername, givenPassword);
        }   
    }

    private void sendPostRequest(String givenUsername, String givenPassword) {

        class SendPostReqAsyncTask extends AsyncTask<String, Void, String>{

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

                String paramUsername = params[0];
                String paramPassword = params[1];

                System.out.println("*** doInBackground ** paramUsername " + paramUsername + " paramPassword :" + paramPassword);

                HttpClient httpClient = new DefaultHttpClient();

                // In a POST request, we don't pass the values in the URL.
                //Therefore we use only the web page URL as the parameter of the HttpPost argument
                HttpPost httpPost = new HttpPost("http://www.nirmana.lk/hec/android/postLogin.php");

                // Because we are not passing values over the URL, we should have a mechanism to pass the values that can be
                //uniquely separate by the other end.
                //To achieve that we use BasicNameValuePair             
                //Things we need to pass with the POST request
                BasicNameValuePair usernameBasicNameValuePair = new BasicNameValuePair("paramUsername", paramUsername);
                BasicNameValuePair passwordBasicNameValuePAir = new BasicNameValuePair("paramPassword", paramPassword);

                // We add the content that we want to pass with the POST request to as name-value pairs
                //Now we put those sending details to an ArrayList with type safe of NameValuePair
                List<NameValuePair> nameValuePairList = new ArrayList<NameValuePair>();
                nameValuePairList.add(usernameBasicNameValuePair);
                nameValuePairList.add(passwordBasicNameValuePAir);

                try {
                    // UrlEncodedFormEntity is an entity composed of a list of url-encoded pairs. 
                    //This is typically useful while sending an HTTP POST request. 
                    UrlEncodedFormEntity urlEncodedFormEntity = new UrlEncodedFormEntity(nameValuePairList);

                    // setEntity() hands the entity (here it is urlEncodedFormEntity) to the request.
                    httpPost.setEntity(urlEncodedFormEntity);

                    try {
                        // HttpResponse is an interface just like HttpPost.
                        //Therefore we can't initialize them
                        HttpResponse httpResponse = httpClient.execute(httpPost);

                        // According to the JAVA API, InputStream constructor do nothing. 
                        //So we can't initialize InputStream although it is not an interface
                        InputStream inputStream = httpResponse.getEntity().getContent();

                        InputStreamReader inputStreamReader = new InputStreamReader(inputStream);

                        BufferedReader bufferedReader = new BufferedReader(inputStreamReader);

                        StringBuilder stringBuilder = new StringBuilder();

                        String bufferedStrChunk = null;

                        while((bufferedStrChunk = bufferedReader.readLine()) != null){
                            stringBuilder.append(bufferedStrChunk);
                        }

                        return stringBuilder.toString();

                    } catch (ClientProtocolException cpe) {
                        System.out.println("First Exception caz of HttpResponese :" + cpe);
                        cpe.printStackTrace();
                    } catch (IOException ioe) {
                        System.out.println("Second Exception caz of HttpResponse :" + ioe);
                        ioe.printStackTrace();
                    }

                } catch (UnsupportedEncodingException uee) {
                    System.out.println("An Exception given because of UrlEncodedFormEntity argument :" + uee);
                    uee.printStackTrace();
                }

                return null;
            }

            @Override
            protected void onPostExecute(String result) {
                super.onPostExecute(result);

                if(result.equals("working")){
                    Toast.makeText(getApplicationContext(), "HTTP POST is working...", Toast.LENGTH_LONG).show();
                }else{
                    Toast.makeText(getApplicationContext(), "Invalid POST req...", Toast.LENGTH_LONG).show();
                }
            }           
        }

        SendPostReqAsyncTask sendPostReqAsyncTask = new SendPostReqAsyncTask();
        sendPostReqAsyncTask.execute(givenUsername, givenPassword);     
    }
}