Android客户端与服务器通信之HttpClient的使用

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关于http协议的介绍，请参考：http://www.cnblogs.com/hanyonglu/archive/2012/02/19/2357842.html ，作者讲解的很清楚。

下面就总结下两种发送带参数的http请求：

两种方法的主要区别是如何携带参数（也就是键值对）的问题，get方法是把要传递的参数直接封装在url中（get方法中的url=要访问的服务器网址信息+需要传递的参数），而post方法是把传递的参数封装在一个list 对象里，然后把这个装有键值对的对象直接绑在httpPost对象上，不是放在url中。

  1 package com.test.http;
  2 
  3 import java.util.List;
  4 
  5 import org.apache.http.HttpResponse;
  6 import org.apache.http.HttpStatus;
  7 import org.apache.http.NameValuePair;
  8 import org.apache.http.client.HttpClient;
  9 import org.apache.http.client.entity.UrlEncodedFormEntity;
 10 import org.apache.http.client.methods.HttpGet;
 11 import org.apache.http.client.methods.HttpPost;
 12 import org.apache.http.impl.client.DefaultHttpClient;
 13 import org.apache.http.params.BasicHttpParams;
 14 import org.apache.http.params.HttpConnectionParams;
 15 import org.apache.http.params.HttpParams;
 16 import org.apache.http.protocol.HTTP;
 17 import org.apache.http.util.EntityUtils;
 18 
 19 /**
 20  *以同步方式发送Http请求
 21  */
 22 public class HttpTools
 23 {
 24     
 25     /**
 26      * 通过GET方式发送请求
 27      * @param url URL地址
 28      * @param params 参数
 29      * @return 
 30      * @throws Exception
 31      */
 32     public String getResultForHttpGet(String url, String params) throws Exception
 33     {
 34         String response = null; //返回信息
 35         //拼接请求URL
 36         if (null!=params&&!params.equals(""))
 37         {
 38             url += "?" + params;
 39         }
 40         
 41         int timeoutConnection = 10000000;  
 42         int timeoutSocket = 5000000;  
 43         //设置网络链接超时
 44         HttpParams httpParameters = new BasicHttpParams();
 45         //设置socket响应超时
 46         HttpConnectionParams.setConnectionTimeout(httpParameters, timeoutConnection);
 47         HttpConnectionParams.setSoTimeout(httpParameters, timeoutSocket); 
 48         
 49         // 构造HttpClient的实例
 50         HttpClient httpClient = new DefaultHttpClient(httpParameters);
 51         
 52         System.out.println("URL = "+url);
 53         // 生成一个请求对象 
 54         HttpGet httpGet = new HttpGet(url);
 55         
 56         try
 57         {
 58             // 使用Http客户端发送请求对象
 59             HttpResponse httpResponse = httpClient.execute(httpGet);
 60             
 61             int statusCode = httpResponse.getStatusLine().getStatusCode();
 62             if (statusCode == HttpStatus.SC_OK) //SC_OK = 200
 63             {
 64                 // 获得返回结果
 65                 response = EntityUtils.toString(httpResponse.getEntity());
 66             }
 67             else
 68             {
 69                 response = "返回码：" + statusCode;
 70             }
 71         } catch (Exception e)
 72         {
 73             throw new Exception(e);
 74         }
 75         
 76         return response;
 77     }
 78 
 79     /**
 80      * 通过POST方式发送请求
 81      * @param url URL地址
 82      * @param params 参数
 83      * @return
 84      * @throws Exception
 85      */
 86     public String getReultForHttpPost(String url, List<NameValuePair> params) throws Exception
 87     {
 88         String response = null;
 89         int timeoutConnection = 300000;  
 90         int timeoutSocket = 500000;  
 91         // 设置网络链接超时 
 92         HttpParams httpParameters = new BasicHttpParams();
 93         // 设置socket响应超时 
 94         HttpConnectionParams.setConnectionTimeout(httpParameters, timeoutConnection);
 95         HttpConnectionParams.setSoTimeout(httpParameters, timeoutSocket);  
 96         // 构造HttpClient的实例
 97         HttpClient httpClient = new DefaultHttpClient(httpParameters);  
 98         HttpPost httpPost = new HttpPost(url);
 99         if (params.size()>=0)
100         {
101             //设置httpPost请求参数
102             httpPost.setEntity(new UrlEncodedFormEntity(params, HTTP.UTF_8));
103         }
104         //使用execute方法发送HTTP Post请求，并返回HttpResponse对象
105         HttpResponse httpResponse = httpClient.execute(httpPost);
106         int statusCode = httpResponse.getStatusLine().getStatusCode();
107         if(statusCode == HttpStatus.SC_OK)
108         {
109             //获得返回结果
110             System.out.println("Post请求成功");
111             response = EntityUtils.toString(httpResponse.getEntity());
112         }
113         else
114         {
115             response = "返回码："+statusCode;
116         }
117         return response;
118     }
119     
120 }

在android客户端，用异步方式实现：

  1 package com.test.http;
  2 
  3 import java.util.ArrayList;
  4 import java.util.List;
  5 
  6 import org.apache.http.NameValuePair;
  7 import org.apache.http.message.BasicNameValuePair;
  8 
  9 import com.test.http.R;
 10 import android.app.Activity;
 11 import android.app.ProgressDialog;
 12 import android.content.Context;
 13 import android.os.AsyncTask;
 14 import android.os.Bundle;
 15 import android.view.View;
 16 import android.view.View.OnClickListener;
 17 import android.widget.Button;
 18 import android.widget.TextView;
 19 
 20 public class TestHttpActivity extends Activity {
 21     private TextView mMsgTxt;
 22     private Button mSendBtn;
 23 
 24     @Override
 25     protected void onCreate(Bundle savedInstanceState) {
 26         super.onCreate(savedInstanceState);
 27         setContentView(R.layout.activity_main);
 28         mMsgTxt = (TextView) findViewById(R.id.txt_show_message);
 29         mSendBtn = (Button) findViewById(R.id.btn_send);
 30         
 31         mSendBtn.setOnClickListener(new OnClickListener() {
 32             @Override
 33             public void onClick(View v) {
 34                 System.out.println("onClick----准备发送请求！");
 35                 post();
 36             }
 37         });
 38     }
 39 
 40     public void post() {
 41         AsynTask asyntask = new AsynTask(this);
 42         asyntask.execute("http://192.168.1.1:8080/TestHttpPost/HttpPost");
 43     }
 44 
 45     class AsynTask extends AsyncTask<String, Integer, String> {
 46         ProgressDialog pdialog;
 47 
 48         public AsynTask(Context context) {
 49             pdialog = new ProgressDialog(context, 0);
 50             pdialog.setCancelable(true);
 51             pdialog.setProgressStyle(ProgressDialog.STYLE_SPINNER);
 52             pdialog.setMessage("取消");
 53             pdialog.show();
 54         }
 55 
 56         @Override
 57         protected String doInBackground(String... params) {
 58             HttpTools httpTools = new HttpTools();
 59             String result = "";
 60             
 61             // NameValuePair对象代表一个键值对  
 62             NameValuePair nameValuePair1 = new BasicNameValuePair("username","test");    
 63             NameValuePair nameValuePair2 = new BasicNameValuePair("password","123456");  
 64             List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();  
 65             //把要发送的键值对参数放到一个list中去  
 66             nameValuePairs.add(nameValuePair1);  
 67             nameValuePairs.add(nameValuePair2);  
 68             
 69             try {
 70 //                /*使用Get方式*/
 71 //                String para = "username=test&password=123456";
 72 //                result = httpTools.getResultForHttpGet(params[0], para);
 73                 
 74                 /*使用Post方式*/
 75                 result = httpTools.getReultForHttpPost(params[0], nameValuePairs);
 76                 
 77                 
 78             } catch (Exception e) {
 79                 e.printStackTrace();
 80             }
 81             return result;
 82         }
 83 
 84         @Override
 85         protected void onCancelled() {
 86 
 87             super.onCancelled();
 88         }
 89 
 90         @Override
 91         protected void onPostExecute(String result) {
 92             mMsgTxt.setText(result);
 93             System.out.println("客户端取到的信息" + result);
 94             pdialog.dismiss();
 95         }
 96 
 97         @Override
 98         protected void onPreExecute() {
 99             mMsgTxt.setText("task start.......");
100         }
101 
102         @Override
103         protected void onProgressUpdate(Integer... values) {
104             System.out.println("" + values[0]);
105             mMsgTxt.setText("" + values[0]);
106             pdialog.setProgress(values[0]);
107         }
108 
109     }
110 
111 }

布局文件测试用，就写的很简单，一个Button，一个TextView.

 1 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 2     xmlns:tools="http://schemas.android.com/tools"
 3     android:layout_width="match_parent"
 4     android:layout_height="match_parent"
 5     android:orientation="vertical" >
 6 
 7     <Button 
 8         android:id="@+id/btn_send"
 9         android:layout_width="match_parent"
10         android:layout_height="wrap_content"
11         android:text="Send"/>
12     <TextView
13         android:id="@+id/txt_show_message"
14         android:layout_width="match_parent"
15         android:layout_height="match_parent"
16         android:text="message"/>
17 
18 </LinearLayout>