HTTPClient模块的HttpGet和HttpPost

浏览数：35 / 时间：2015年06月09日

? ? 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

[java]?view plaincopy?
?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;??
????}??

?????????????? 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。

[java]?view plaincopy?
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));??
????????????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;??
????}??

????????? 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。

[java]?view plaincopy?
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??
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由于是联网，在AndroidManifest.xml中添加网络连接的权限??
<uses-permission?android:name="android.permission.INTERNET"/>??