使用HttpClient对象来发送请求、接受响应步骤：
创建HttpClient对象
如果要发送GET请求，创建HttpGet对象；如果是POST请求，则创建HttpPost对象。
如果需要添加参数，对于HttpGet直接在构造URL的时候填入参数。对于POST请求，使用setEntity(HttpEntity entity)方法来设置
调用HttpClient对象的execute（HttpUriRequest request）发送请求，此方法返回一个HttpResponse
调用HttpResponse的getALLHeaders()、getHeaders(String name)等方法可获取服务器响应头；调用HttpResponse的getEntity（）方法可获取HttpEntity对象，该对象包装了服务器响应内容。
注意：
不少地方说可以使用HttpGet和HttpPost共同的setParams(HttpParams params)方法添加请求参数，但是我没有设置成功，网上搜索发现好多人也没成功。Even Apache’s official example uses URIBuilder’s setParameter method to build the params out in the URI，所以没有使用这种方法.
GET请求Demo：
public class MainActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
TextView textViewShow = (TextView) findViewById(R.id.showText);
//直接在URL后添加请求参数
String url = "http://192.168.1.103/index.php?get1=hello&get2=bay";
try {
// 创建DefaultHttpClient对象
HttpClient httpclient = new DefaultHttpClient();
// 创建一个HttpGet对象
HttpGet get = new HttpGet(url);
// 获取HttpResponse对象
HttpResponse response = httpclient.execute(get);
//判断是否链接成功
if (response.getStatusLine().getStatusCode() == 200) {
//实体转换为字符串
String content = EntityUtils.toString(response.getEntity(),"utf-8");
textViewShow.setText(content);
}else{
textViewShow.setText("网络错误");
}
} catch (ClientProtocolException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}POST请求Demo：
public class MainActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
TextView textViewShow = (TextView) findViewById(R.id.showText);
String url = "http://192.168.1.103/index.php";
HttpClient httpClient = new DefaultHttpClient();
try {
HttpPost post = new HttpPost(url);
List params = new ArrayList();
params.add(new BasicNameValuePair("get1", "hello"));
params.add(new BasicNameValuePair("get2", "usrl"));
post.setEntity(new UrlEncodedFormEntity(params, HTTP.UTF_8));
HttpResponse response = httpClient.execute(post);
if(response.getStatusLine().getStatusCode() ==200){
String content = EntityUtils.toString(response.getEntity(),"utf-8");
textViewShow.setText(content);
}else{
textViewShow.setText("网络问题");
}
} catch (UnsupportedEncodingException e) {
// TODO Auto-generated catch block
textViewShow.setText("UnsupportedEncodingException");
} catch (ClientProtocolException e) {
// TODO Auto-generated catch block
textViewShow.setText("ClientProtocolException");
} catch (IOException e) {
// TODO Auto-generated catch block
textViewShow.setText("IOException");
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}