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Android 网络操作常用的两个类

 Android SDK集成了Apache HttpClient模块。要注意的是,这里的Apache HttpClient模块是HttpClient 4.0(org.apache.http.*),而不是常见的 Jakarta Commons HttpClient 3.x(org.apache.commons.httpclient.*)。

           HttpClient常用HttpGet和HttpPost这两个类,分别对应Get方式和Post方式。

           无论是使用HttpGet,还是使用HttpPost,都必须通过如下3步来访问HTTP资源。
         
            1.创建HttpGet或HttpPost对象,将要请求的URL通过构造方法传入HttpGet或HttpPost对象。

           2.使用DefaultHttpClient类的execute方法发送HTTP GET或HTTP POST请求,并返回HttpResponse对象。

           3.通过HttpResponse接口的getEntity方法返回响应信息,并进行相应的处理。

           如果使用HttpPost方法提交HTTP POST请求,则需要使用HttpPost类的setEntity方法设置请求参数。参数则必须用NameValuePair[]数组存储。


下面给出一些实例:

 
Get方式:

[java]  // HttpGet方式请求    
public static void requestByHttpGet() throws Exception {   
    String path = "https://reg.163.com/logins.jsp?id=helloworld&pwd=android";   
    // 新建HttpGet对象    
    HttpGet httpGet = new HttpGet(path);   
    // 获取HttpClient对象    
    HttpClient httpClient = new DefaultHttpClient();   
    // 获取HttpResponse实例    
    HttpResponse httpResp = httpClient.execute(httpGet);   
    // 判断是够请求成功    
    if (httpResp.getStatusLine().getStatusCode() == HTTP_200) {   
        // 获取返回的数据    
        String result = EntityUtils.toString(httpResp.getEntity(), "UTF-8");   
        Log.i(TAG_HTTPGET, "HttpGet方式请求成功,返回数据如下:");   
        Log.i(TAG_HTTPGET, result);   
    } else {   
        Log.i(TAG_HTTPGET, "HttpGet方式请求失败");   
    }   
}   

// HttpGet方式请求 
public static void requestByHttpGet() throws Exception { 
    String path = "https://reg.163.com/logins.jsp?id=helloworld&pwd=android"; 
    // 新建HttpGet对象 
    HttpGet httpGet = new HttpGet(path); 
    // 获取HttpClient对象 
    HttpClient httpClient = new DefaultHttpClient(); 
    // 获取HttpResponse实例 
    HttpResponse httpResp = httpClient.execute(httpGet); 
    // 判断是够请求成功 
    if (httpResp.getStatusLine().getStatusCode() == HTTP_200) { 
        // 获取返回的数据 
        String result = EntityUtils.toString(httpResp.getEntity(), "UTF-8"); 
        Log.i(TAG_HTTPGET, "HttpGet方式请求成功,返回数据如下:"); 
        Log.i(TAG_HTTPGET, result); 
    } else { 
        Log.i(TAG_HTTPGET, "HttpGet方式请求失败"); 
    } 

[java]  public String doGet()   
    {   
        String uriAPI = "http://XXXXX?str=I+am+get+String";   
        String result= "";   
//      HttpGet httpRequst = new HttpGet(URI uri);    
//      HttpGet httpRequst = new HttpGet(String uri);    
//      创建HttpGet或HttpPost对象,将要请求的URL通过构造方法传入HttpGet或HttpPost对象。    
        HttpGet httpRequst = new HttpGet(uriAPI);   
   
//      new DefaultHttpClient().execute(HttpUriRequst requst);    
        try {   
   //使用DefaultHttpClient类的execute方法发送HTTP GET请求,并返回HttpResponse对象。    
            HttpResponse httpResponse = new DefaultHttpClient().execute(httpRequst);//其中HttpGet是HttpUriRequst的子类    
            if(httpResponse.getStatusLine().getStatusCode() == 200)   
            {   
                HttpEntity httpEntity = httpResponse.getEntity();   
                result = EntityUtils.toString(httpEntity);//取出应答字符串    
            // 一般来说都要删除多余的字符     
                result.replaceAll("\r", "");//去掉返回结果中的"\r"字符,否则会在结果字符串后面显示一个小方格      
            }   
                   else    
                        httpRequst.abort();   
           } catch (ClientProtocolException e) {   
            // TODO Auto-generated catch block    
            e.printStackTrace();   
            result = e.getMessage().toString();   
        } catch (IOException e) {   
            // TODO Auto-generated catch block    
            e.printStackTrace();   
            result = e.getMessage().toString();   
        }&

补充:移动开发 , Android ,
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