HttpClient常用HttpGet和HttpPost

 Android SDK集成了Apache HttpClient模塊。要注意的是，這裏的Apache HttpClient模塊是HttpClient 4.0（org.apache.http.*），而不是常見的Jakarta Commons HttpClient 3.x（org.apache.commons.httpclient.*）。

           HttpClient常用HttpGet和HttpPost這兩個類，分別對應Get方式和Post方式。

           無論是使用HttpGet，還是使用HttpPost，都必須通過如下3步來訪問HTTP資源。

           1.創建HttpGet或HttpPost對象，將要請求的URL通過構造方法傳入HttpGet或HttpPost對象。

           2.使用DefaultHttpClient類的execute方法發送HTTP GET或HTTP POST請求，並返回HttpResponse對象。

           3.通過HttpResponse接口的getEntity方法返回響應信息，並進行相應的處理。

           如果使用HttpPost方法提交HTTP POST請求，則需要使用HttpPost類的setEntity方法設置請求參數。參數則必須用NameValuePair[]數組存儲。

          

           HttpGet

   

 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);
//      創建HttpGet或HttpPost對象，將要請求的URL通過構造方法傳入HttpGet或HttpPost對象。
        HttpGet httpRequst = new HttpGet(uriAPI);

//      new DefaultHttpClient().execute(HttpUriRequst requst);
        try {
   //使用DefaultHttpClient類的execute方法發送HTTP GET請求，並返回HttpResponse對象。
            HttpResponse httpResponse = new DefaultHttpClient().execute(httpRequst);//其中HttpGet是HttpUriRequst的子類
            if(httpResponse.getStatusLine().getStatusCode() == 200)
            {
                HttpEntity httpEntity = httpResponse.getEntity();
                result = EntityUtils.toString(httpEntity);//取出應答字符串
            // 一般來說都要刪除多餘的字符
                result.replaceAll("\r", "");//去掉返回結果中的"\r"字符，否則會在結果字符串後面顯示一個小方格
            }
                   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();
        }
        return result;
    }

cookie等參數的設置

  //設置httpGet的參數信息

        httpGet.setHeader("Accept", "Accept text/html,application/xhtml

+xml,application/xml;q=0.9,*/*;q=0.8");

        httpGet.setHeader("Accept-Charset", "GB2312,utf-8;q=0.7,*;q=0.7");

        httpGet.setHeader("Accept-Encoding", "gzip, deflate");

        httpGet.setHeader("Accept-Language", "zh-cn,zh;q=0.5");

        httpGet.setHeader("Connection", "keep-alive");

        httpGet.setHeader("Cookie",

"__utma=226521935.73826752.1323672782.1325068020.1328770420.6;");

        httpGet.setHeader("Host", "www.cnblogs.com");

        httpGet.setHeader("refer", "http://www.baidu.com/s?

tn=monline_5_dg&bs=httpclient4+MultiThreadedHttpConnectionManager");

        httpGet.setHeader("User-Agent", "Mozilla/5.0 (Windows NT 6.1; rv:6.0.2)

Gecko/20100101 Firefox/6.0.2");

               HttpPost

              如果使用HttpPost方法提交HTTP POST請求，則需要使用HttpPost類的setEntity方法設置請求參數。參數則必須用NameValuePair[]數組存儲。或者用 參數=值&參數=值字符串的類型

數組參數類型----如果數組類型返回302  則改用 字符串參數類型

public String doPost()
    {
        String uriAPI = "http://XXXXXX";//Post方式沒有參數在這裏
        String result = "";
        HttpPost httpRequst = new HttpPost(uriAPI);//創建HttpPost對象

        List <NameValuePair> params = new ArrayList<NameValuePair>();
        params.add(new BasicNameValuePair("str", "I am Post String"));


        try {
            httpRequst.setEntity(new UrlEncodedFormEntity(params,HTTP.UTF_8));
//httpRequst.setEntity(new StringEntity("{\"id\":0,\"method\":\"LoadCompanyAllInfo\",\"params\":[{\"CompanyId\":4055,\"CompanyName\":\"\"}]}"));
            HttpResponse httpResponse = new DefaultHttpClient().execute(httpRequst);
            if(httpResponse.getStatusLine().getStatusCode() == 200)
            {
                HttpEntity httpEntity = httpResponse.getEntity();
                result = EntityUtils.toString(httpEntity);//取出應答字符串
            }
        } catch (UnsupportedEncodingException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
            result = e.getMessage().toString();
        }
        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();
        }
        return result;
    }

字符串參數類型

String result = "";
        HttpPost httpRequst = new HttpPost(url);// 創建HttpPost對象

        try {


            String param="__VIEWSTATE=D&__EVENTTARGET=AspNetPager1&__EVENTARGUMENT=5&AspNetPager1_input=2";


             StringEntity entity = new StringEntity(param);
             entity.setContentType("application/x-www-form-urlencoded");
             entity.setContentEncoding("gb2312");
             httpRequst.setEntity(entity);

            HttpResponse httpResponse = new DefaultHttpClient()
                    .execute(httpRequst);
            System.out.println(httpResponse.getStatusLine().getStatusCode());
            if (httpResponse.getStatusLine().getStatusCode() == 200) {
                HttpEntity httpEntity = httpResponse.getEntity();
                result = EntityUtils.toString(httpEntity);// 取出應答字符串
                System.out.println(result);
            }
        } catch (UnsupportedEncodingException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
            result = e.getMessage().toString();
        } 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();
        }

          以發送連接請求時，需要設置鏈接超時和請求超時等參數，否則會長期停止或者崩潰。

  HttpParams httpParameters = new BasicHttpParams();
HttpConnectionParams.setConnectionTimeout(httpParameters, 10*1000);//設置請求超時10秒
HttpConnectionParams.setSoTimeout(httpParameters, 10*1000); //設置等待數據超時10秒
HttpConnectionParams.setSocketBufferSize(params, 8192);
HttpClient httpclient = new DefaultHttpClient(httpParameters); //此時構造DefaultHttpClient時將參數傳入

原文地址：http://blog.csdn.net/zzq900503/article/details/17320807