5 . for Android = >

org.apache.http类和AndroidHttpClient类在Android 5.1中已弃用。这些类不再被维护，你应该尽快将任何使用这些api的应用程序代码迁移到URLConnection类。

https://developer.android.com/about/versions/android-5.1.html#http

考虑使用HttpUrlConnection共享我的代码

public String  performPostCall(String requestURL,
        HashMap<String, String> postDataParams) {

    URL url;
    String response = "";
    try {
        url = new URL(requestURL);

        HttpURLConnection conn = (HttpURLConnection) url.openConnection();
        conn.setReadTimeout(15000);
        conn.setConnectTimeout(15000);
        conn.setRequestMethod("GET");
        conn.setDoInput(true);
        conn.setDoOutput(true);


        OutputStream os = conn.getOutputStream();
        BufferedWriter writer = new BufferedWriter(
                new OutputStreamWriter(os, "UTF-8"));
        writer.write(getPostDataString(postDataParams));

        writer.flush();
        writer.close();
        os.close();
        int responseCode=conn.getResponseCode();

        if (responseCode == HttpsURLConnection.HTTP_OK) {
            String line;
            BufferedReader br=new BufferedReader(new InputStreamReader(conn.getInputStream()));
            while ((line=br.readLine()) != null) {
                response+=line;
            }
        }
        else {
            response="";    

        }
    } catch (Exception e) {
        e.printStackTrace();
    }

    return response;
}

...

private String getPostDataString(HashMap<String, String> params) throws UnsupportedEncodingException{
        StringBuilder result = new StringBuilder();
        boolean first = true;
        for(Map.Entry<String, String> entry : params.entrySet()){
            if (first)
                first = false;
            else
                result.append("&");

            result.append(URLEncoder.encode(entry.getKey(), "UTF-8"));
            result.append("=");
            result.append(URLEncoder.encode(entry.getValue(), "UTF-8"));
        }

        return result.toString();
    }

你也可以张贴方法:

conn.setRequestMethod("POST");

更新21/02/2016

对于post request with json，请看这个例子:

public class Empty extends
        AsyncTask<Void, Void, Boolean> {

    String urlString = "http://www.yoursite.com/";

    private final String TAG = "post json example";
    private Context context;

    private int advertisementId;

    public Empty(Context contex, int advertisementId) {

        this.context = contex;
        this.advertisementId = advertisementId;
    }

    @Override
    protected void onPreExecute() {
        Log.e(TAG, "1 - RequestVoteTask is about to start...");

    }

    @Override
    protected Boolean doInBackground(Void... params) {
        boolean status = false;

        String response = "";
        Log.e(TAG, "2 - pre Request to response...");

        try {
            response = performPostCall(urlString, new HashMap<String, String>() {

                        private static final long serialVersionUID = 1L;

                        {
                            put("Accept", "application/json");
                            put("Content-Type", "application/json");
                        }
                    });
            Log.e(TAG, "3 - give Response...");
            Log.e(TAG, "4 " + response.toString());
        } catch (Exception e) {
            // displayLoding(false);

            Log.e(TAG, "Error ...");
        }
        Log.e(TAG, "5 - after Response...");

        if (!response.equalsIgnoreCase("")) {
            try {
                Log.e(TAG, "6 - response !empty...");
                //
                JSONObject jRoot = new JSONObject(response);
                JSONObject d = jRoot.getJSONObject("d");

                int ResultType = d.getInt("ResultType");
                Log.e("ResultType", ResultType + "");

                if (ResultType == 1) {

                    status = true;

                }

            } catch (JSONException e) {
                // displayLoding(false);
                // e.printStackTrace();
                Log.e(TAG, "Error " + e.getMessage());
            } finally {

            }
        } else {
            Log.e(TAG, "6 - response is empty...");

            status = false;
        }

        return status;
    }

    @Override
    protected void onPostExecute(Boolean result) {
        //
        Log.e(TAG, "7 - onPostExecute ...");

        if (result) {
            Log.e(TAG, "8 - Update UI ...");

            // setUpdateUI(adv);
        } else {
            Log.e(TAG, "8 - Finish ...");

            // displayLoding(false);
            // finish();
        }

    }

    public String performPostCall(String requestURL,
                                  HashMap<String, String> postDataParams) {

        URL url;
        String response = "";
        try {
            url = new URL(requestURL);

            HttpURLConnection conn = (HttpURLConnection) url.openConnection();
            conn.setReadTimeout(context.getResources().getInteger(
                    R.integer.maximum_timeout_to_server));
            conn.setConnectTimeout(context.getResources().getInteger(
                    R.integer.maximum_timeout_to_server));
            conn.setRequestMethod("POST");
            conn.setDoInput(true);
            conn.setDoOutput(true);

            conn.setRequestProperty("Content-Type", "application/json");

            Log.e(TAG, "11 - url : " + requestURL);

            /*
             * JSON
             */

            JSONObject root = new JSONObject();
            //
            String token = Static.getPrefsToken(context);

            root.put("securityInfo", Static.getSecurityInfo(context));
            root.put("advertisementId", advertisementId);

            Log.e(TAG, "12 - root : " + root.toString());

            String str = root.toString();
            byte[] outputBytes = str.getBytes("UTF-8");
            OutputStream os = conn.getOutputStream();
            os.write(outputBytes);

            int responseCode = conn.getResponseCode();

            Log.e(TAG, "13 - responseCode : " + responseCode);

            if (responseCode == HttpsURLConnection.HTTP_OK) {
                Log.e(TAG, "14 - HTTP_OK");

                String line;
                BufferedReader br = new BufferedReader(new InputStreamReader(
                        conn.getInputStream()));
                while ((line = br.readLine()) != null) {
                    response += line;
                }
            } else {
                Log.e(TAG, "14 - False - HTTP_OK");
                response = "";
            }
        } catch (Exception e) {
            e.printStackTrace();
        }

        return response;
    }
}

更新24/08/2016

使用一些最好的库，例如:

改造 凌空抽射

因为:

避免使用HttpUrlConnection和HttpClient

在较低的API级别上(主要是在Gingerbread和Froyo上)，httppurlconnection和HttpClient还远远不够完美

并且避免AsyncTask 他们要快得多 他们会缓存所有东西

自从Honeycomb (API 11)引入以来，强制在不同于主线程的单独线程上执行网络操作

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。

如果你只是想把数据附加到Url，你可以通过使用httppurlconnection来实现，因为HttpClient现在已经弃用了。 更好的方法是使用像-这样的库

凌空抽射 改造

我们可以将数据发送到php脚本，并通过使用AsyncTask类执行的代码来获取结果并显示它。

    private class LongOperation  extends AsyncTask<String, Void, Void> {

    // Required initialization


    private String Content;
    private String Error = null;
    private ProgressDialog Dialog = new ProgressDialog(Login.this);
    String data ="";
    int sizeData = 0;



    protected void onPreExecute() {
        // NOTE: You can call UI Element here.

        //Start Progress Dialog (Message)

        Dialog.setMessage("Please wait..");
        Dialog.show();
        Dialog.setCancelable(false);
        Dialog.setCanceledOnTouchOutside(false);

        try{
            // Set Request parameter
            data +="&" + URLEncoder.encode("username", "UTF-8") + "="+edittext.getText();



        } catch (UnsupportedEncodingException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

    }

    // Call after onPreExecute method
    protected Void doInBackground(String... urls) {

        /************ Make Post Call To Web Server ***********/
        BufferedReader reader=null;

        // Send data
        try
        {

            // Defined URL  where to send data
            URL url = new URL(urls[0]);

            // Send POST data request

            URLConnection conn = url.openConnection();

            conn.setConnectTimeout(5000);//define connection timeout 
            conn.setReadTimeout(5000);//define read timeout
            conn.setDoOutput(true);
            OutputStreamWriter wr = new OutputStreamWriter(conn.getOutputStream());
            wr.write( data );
            wr.flush();

            // Get the server response

            reader = new BufferedReader(new InputStreamReader(conn.getInputStream()));
            StringBuilder sb = new StringBuilder();
            String line = null;



            // Read Server Response
            while((line = reader.readLine()) != null)
            {
                // Append server response in string
                sb.append(line + " ");
            }

            // Append Server Response To Content String
            Content = sb.toString();


        }
        catch(Exception ex)
        {
            Error = ex.getMessage();
        }
        finally
        {
            try
            {

                reader.close();
            }

            catch(Exception ex) {}
        }


        return null;
    }

    protected void onPostExecute(Void unused) {
        // NOTE: You can call UI Element here.

        // Close progress dialog
        Dialog.dismiss();

        if (Error != null) {

                Toast.makeText(getApplicationContext(),"Error encountered",Toast.LENGTH_LONG).show();



        }
        else {




            try {

                JSONObject jsonRootObject = new JSONObject(Content);


                JSONObject json2 =jsonRootObject.getJSONObject("jsonkey");//pass jsonkey here


                String id =json2.optString("id").toString();//parse json to string through parameters


     //the result is stored in string id. you can display it now


            } catch (JSONException e) {e.printStackTrace();}


        }

    }

}

但是使用诸如volley或retrofit之类的库是更好的选择，因为Asynctask类和HttpurlConnection相比库更慢。此外，库将获取所有内容，也更快。

@primpop的答案，我会添加如何转换字符串中的响应:

HttpResponse response = client.execute(request);
HttpEntity entity = response.getEntity();
if (entity != null) {
    InputStream instream = entity.getContent();

    String result = RestClient.convertStreamToString(instream);
    Log.i("Read from server", result);
}

下面是一个convertStramToString的例子。

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>

使用来自Square的开源okHttp库。okHttp适用于Android 2.3及以上版本，并在GitHub上拥有Apache 2.0许可证。

发送POST数据就像在AsyncTask中添加以下内容一样简单:

OkHttpClient client = new OkHttpClient();
RequestBody formBody = new FormBody.Builder()
                      .add("email", emailString) // A sample POST field
                      .add("comment", commentString) // Another sample POST field
                      .build();
Request request = new Request.Builder()
                 .url("https://yourdomain.org/callback.php") // The URL to send the data to
                 .post(formBody)
                 .build();

okHttp在maven上也有一个命名空间，所以将它添加到Android Studio项目很简单。只需将编译'com.squareup.okhttp3:okhttp:3.11.0'添加到应用程序的build.gradle中。

完整的代码

在你的活动中添加以下内容:

public class CallAPI extends AsyncTask<String, String, String> {

    String emailString;
    String commentString;

    public CallAPI(String email, String commnt){
           emailString = email;
           commentString = commnt;
    }

    @Override
    protected void onPreExecute() {
        super.onPreExecute();
    }

    @Override
    protected String doInBackground(String... params) {
        OkHttpClient client = new OkHttpClient();
        RequestBody formBody = new FormBody.Builder()
                      .add("email", emailString) // A sample POST field
                      .add("comment", commentString) // Another sample POST field
                      .build();
        Request request = new Request.Builder()
                 .url("https://yourdomain.org/callback.php") // The URL to send the data to
                 .post(formBody)
                 .build();
        return "";
    }

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

并将其称为using:

new CallAPI(emailString, commentString).execute();