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
//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
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
原文链接:
http://blog.csdn.net/caesardadi/article/details/8621595