HttpClient常用HttpGet和HttpPost

 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。

          

           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);
//      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();
        }
        return result;
    }

cookie等参数的设置

  //设置httpGet的参数信息

        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。或者用 参数=值&参数=值字符串的类型

数组参数类型----如果数组类型返回302  则改用 字符串参数类型

public String doPost()
    {
        String uriAPI = "http://XXXXXX";//Post方式没有参数在这里
        String result = "";
        HttpPost httpRequst = new HttpPost(uriAPI);//创建HttpPost对象

        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);//取出应答字符串
            }
        } 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;
    }

字符串参数类型

String result = "";
        HttpPost httpRequst = new HttpPost(url);// 创建HttpPost对象

        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);// 取出应答字符串
                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();
        }

          以发送连接请求时，需要设置链接超时和请求超时等参数，否则会长期停止或者崩溃。

  HttpParams httpParameters = new BasicHttpParams();
HttpConnectionParams.setConnectionTimeout(httpParameters, 10*1000);//设置请求超时10秒
HttpConnectionParams.setSoTimeout(httpParameters, 10*1000); //设置等待数据超时10秒
HttpConnectionParams.setSocketBufferSize(params, 8192);
HttpClient httpclient = new DefaultHttpClient(httpParameters); //此时构造DefaultHttpClient时将参数传入

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