android 发送post请求

代码如下：

 try {
    HttpClient client = new DefaultHttpClient();
    HttpPost httpPost = new HttpPost(url);  
    ArrayList<BasicNameValuePair> pairs = new ArrayList<BasicNameValuePair>();  
    Set<String> keys = params.keySet();  
    for(Iterator<String> i = keys.iterator(); i.hasNext();) {  
                String key = (String)i.next();  
                   pairs.add(new BasicNameValuePair(key, params.get(key)));  
             }  
    UrlEncodedFormEntity p_entity = new UrlEncodedFormEntity(pairs, "utf-8"); 
    httpPost.setEntity(p_entity);
    HttpResponse response = client.execute(httpPost); 
    HttpEntity entity = response.getEntity();  
    content = entity.getContent();  

在执行到HttpResponse response = client.execute(httpPost); 就出错了，求大神看下，或者给个简单的例子。

---

我只是来推荐一个第三方库的。。

http://loopj.com/android-async-http/

用它用来Post一个表单就这么简单：

RequestParams params = new RequestParams();
params.put("key", "value");
params.put("more", "data");

AsyncHttpClient client = new AsyncHttpClient();
client.post("http://www.google.com", params， new AsyncHttpResponseHandler() {
    @Override
    public void onSuccess(String response) {
        System.out.println(response);
    }
});

可以免去写一些代码，套一堆try-catch块，写处理网络线程和UI线程交互的代码的困扰。

Instagram都在用这个库。。。