三种POST和GET的提交方式

      向服务器提交数据有两种方式，post和get。两者的区别主要有三点，安全性、长度限制、数据结构。其中get请求安全性相比较而言较差，数据长度受浏览器地址栏限制，没有方法体。两种都是较为重要的数据提交方式。现简单介绍一下三种post和get的提交方式。无论是哪种方法实现post和get，get 的访问路径都要携带数据，而post提交是把数据放在方法体中。

     普通方法实现get/post提交：    

     严格遵照Http协议进行数据传输。在安卓开发环境下，由于主线程不能进行网络访问，因此需要在开启一个子线程向服务器提交数据。为了更加直观的观察数据，可以在程序屏幕上显示服务器反馈信息。又由于子线程无法更改UI界面，因此需要引入Hnndler代理器。实现get/post提交基本步骤就是，获取URL路径，根据路径得到Http连接，用HttpURLConnection对象设置相关的http配置信息、提交方式以及获取反馈码。当响应码为200时表示提交成功，可以通过HttpURLConnection以流的形式获取反馈信息。 

         普通GRT提交方式：

public void load(View view){
		final String qq = et_qq.getText().toString().trim();
		final String pwd = et_pwd.getText().toString().trim();
		if (TextUtils.isEmpty(qq) || TextUtils.isEmpty(pwd)) {
			Toast.makeText(MainActivity.this, "qq号或密码为空", 0).show();
	    	return;
		}
		final String path = "http://192.168.1.114:8080/qqload/qqload?qq=" + qq
				+ "&pwd=" + pwd;
		new Thread() {
			public void run() {
				try {
					URL url = new URL(path);
					HttpURLConnection conn = (HttpURLConnection) url
							.openConnection();
					conn.setRequestMethod("GET");
					conn.setReadTimeout(5000);
					int code = conn.getResponseCode();
					if (code == 200) {
						InputStream is = conn.getInputStream();
						String result = StreamTools.ReadStream(is);
						Message msg = Message.obtain();
						msg.what = SUCCESS;
						msg.obj = result;
						handler.sendMessage(msg);
					} else {
						Message msg = Message.obtain();
						msg.what = ERROR1;
						handler.sendMessage(msg);
					}
				} catch (Exception e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
					Message msg = Message.obtain();
					msg.what = ERROR2;
					handler.sendMessage(msg);
				}
			}
		}.start();
	}

　　

         普通POST提交方式：

public void load(View view){
        final String qq = et_qq.getText().toString().trim();
        final String pwd = et_pwd.getText().toString().trim();
        if (TextUtils.isEmpty(qq) || TextUtils.isEmpty(pwd)) {
            Toast.makeText(MainActivity.this, "qq号或密码为空", 0).show();
            return;
        }
        final String path = "http://192.168.1.114:8080/qqload/qqload";
        new Thread() {
            public void run() {
                try {
                    URL url = new URL(path);
                    HttpURLConnection conn = (HttpURLConnection) url
                            .openConnection();
                    conn.setRequestMethod("POST");
                    conn.setReadTimeout(5000);
                    conn.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
                    String data = "qq="+URLEncoder.encode(qq,"utf-8")+"&pwd=" + URLEncoder.encode(pwd,"utf-8"); 
                    conn.setRequestProperty("Content-Length",String.valueOf(data.length()));
                    conn.setDoOutput(true);
                    conn.getOutputStream().write(data.getBytes());
                    int code = conn.getResponseCode();
                    if (code == 200) {
                        InputStream is = conn.getInputStream();
                        String result = StreamTools.ReadStream(is);
                        Message msg = Message.obtain();
                        msg.what = SUCCESS;
                        msg.obj = result;
                        handler.sendMessage(msg);
                    } else {
                        Message msg = Message.obtain();
                        msg.what = ERROR1;
                        handler.sendMessage(msg);
                    }
                } catch (Exception e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                    Message msg = Message.obtain();
                    msg.what = ERROR2;
                    handler.sendMessage(msg);
                }
            }
        }.start();
    }

       用httpclien实现get/post提交的只需要一下几个步骤：

       1.     创建HttpClient对象，实现打开浏览器的功能

                       HttpClient client = new DefaultHttpClient();

　　 2.     输入地址或者数据 ，用到HttpGet()或HttpPost(),传入要访问的路径，得到HttpGet或HttpPost对象。

      　　　　　　HttpGet  httpGet = new HttpGet(path);

　　3.     把获得的HttpGet或HttpPost对象发送到服务器，实现敲回车的功能，得到HttpResponse对象。

　　　　　　　　HttpResponse response = client.execute(httpGet);

　　4.     得到HttpResponse对象获取状态行中的状态码，判断状态码状态码。

 　　　　　　　　int code = response.getStatusLine().getStatusCode();

　　5.     同样用HttpResponse对象获取相应内容，存入流对象。最后将得到的流对象转为字符串进行显示。

　　　　　　　　　InputStream is = response.getEntity().getContent();

　　　　其中要注意的一点是用post请求时要传递值所以要多出一个步骤。具体而言，先创建一个list集合，集合的泛型用NameValuePair表示，类似于键值对的形式存储要传递的数据。接着向集合中添加要提交数据。最后用HttpPost对象把集合存入请求体中。

           用HttpClient实现GET提交：

public void load(View view){
        final String qq = et_qq.getText().toString().trim();
        final String pwd = et_pwd.getText().toString().trim();
        if (TextUtils.isEmpty(qq) || TextUtils.isEmpty(pwd)) {
            Toast.makeText(MainActivity.this, "qq号或密码为空", 0).show();
            return;
        }
        final String path = "http://192.168.1.114:8080/qqload/qqload?qq=" + qq
                + "&pwd=" + pwd;
        new Thread() {
            public void run() {
                try {
                    HttpClient client = new DefaultHttpClient();
                    HttpGet httpget = new HttpGet(path);
                    HttpResponse response = client.execute(httpget);
                    int code = response.getStatusLine().getStatusCode();
                    if (code == 200) {
                        InputStream is = response.getEntity().getContent();
                        String result = StreamTools.ReadStream(is);
                        Message msg = Message.obtain();
                        msg.what = SUCCESS;
                        msg.obj = result;
                        handler.sendMessage(msg);
                    } else {
                        Message msg = Message.obtain();
                        msg.what = ERROR1;
                        handler.sendMessage(msg);
                    }
                } catch (Exception e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                    Message msg = Message.obtain();
                    msg.what = ERROR2;
                    handler.sendMessage(msg);
                }
            }
        }.start();
    }

             用HttpClient实现POST提交：    

    public void load(View view){
        final String qq = et_qq.getText().toString().trim();
        final String pwd = et_pwd.getText().toString().trim();
        if (TextUtils.isEmpty(qq) || TextUtils.isEmpty(pwd)) {
            Toast.makeText(MainActivity.this, "qq号或密码为空", 0).show();
            return;
        }
        final String path = "http://192.168.1.114:8080/qqload/qqload";
        new Thread() {
            public void run() {
                try {
                    HttpClient client = new DefaultHttpClient();
                    HttpPost httppost = new HttpPost(path);
                    List<NameValuePair> parameter = new ArrayList();
                    parameter.add(new BasicNameValuePair("qq", qq));
                    parameter.add(new BasicNameValuePair("pwd", pwd));
                    httppost.setEntity(new UrlEncodedFormEntity(parameter,"utf-8"));
                    HttpResponse response = client.execute(httppost);
                    int code = response.getStatusLine().getStatusCode();
                    if (code == 200) {
                        InputStream is = response.getEntity().getContent();
                        String result = StreamTools.ReadStream(is);
                        Message msg = Message.obtain();
                        msg.what = SUCCESS;
                        msg.obj = result;
                        handler.sendMessage(msg);
                    } else {
                        Message msg = Message.obtain();
                        msg.what = ERROR1;
                        handler.sendMessage(msg);
                    }
                } catch (Exception e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                    Message msg = Message.obtain();
                    msg.what = ERROR2;
                    handler.sendMessage(msg);
                }
            }
        }.start();
    }

         

        使用开源框架实现get/post提交：

        利用框架实现get/post提交不需要再开启子线程。直接在主线程进行get/post的提交，大大的减少了工作量。但操作前需要导包。然后直接创建一个AsyncHttpClient对象，用AsyncHttpClient对象的post方法和get方法，发送请求，并在AsyncHttpResponseHandler()对象中获得相应信息。同样若是post请求，仍旧需要传递值。这里可以用RequestParams对象添加要传递的值。

         在文件下添加jar包：

                           

           用开源框架实现GET提交：

public void load(View view){
        final String qq = et_qq.getText().toString().trim();
        final String pwd = et_pwd.getText().toString().trim();
        if (TextUtils.isEmpty(qq) || TextUtils.isEmpty(pwd)) {
            Toast.makeText(MainActivity.this, "qq号或密码为空", 0).show();
            return;
        }
        final String path = "http://192.168.1.114:8080/qqload/qqload?qq=" + qq
                + "&pwd=" + pwd;
        AsyncHttpClient client = new AsyncHttpClient();
        client.get(path, new AsyncHttpResponseHandler() {
            
            @Override
            public void onSuccess(int statusCode, Header[] headers, byte[] responseBody) {
                // TODO Auto-generated method stub
                tv_result.setText(new String(responseBody));
            }
            
            @Override
            public void onFailure(int statusCode, Header[] headers,
                    byte[] responseBody, Throwable error) {
                // TODO Auto-generated method stub
                tv_result.setText("错误原因：" + new String(responseBody));
            }
        });
    }

     

        用开源框架实现POST请求：

    public void load(View view){
        final String qq = et_qq.getText().toString().trim();
        final String pwd = et_pwd.getText().toString().trim();
        if (TextUtils.isEmpty(qq) || TextUtils.isEmpty(pwd)) {
            Toast.makeText(MainActivity.this, "qq号或密码为空", 0).show();
            return;
        }
        final String path = "http://192.168.1.114:8080/qqload/qqload";
        AsyncHttpClient client = new AsyncHttpClient();
        RequestParams params = new RequestParams();
        params.add("qq", qq);
        params.add("pwd", pwd);
        client.post(path,params,new AsyncHttpResponseHandler() {
            
            @Override
            public void onSuccess(int statusCode, Header[] headers, byte[] responseBody) {
                // TODO Auto-generated method stub
                tv_result.setText(new String(responseBody));
            }
            
            @Override
            public void onFailure(int statusCode, Header[] headers,
                    byte[] responseBody, Throwable error) {
                // TODO Auto-generated method stub
                tv_result.setText(new String(responseBody));
            }
        });
    }

       

          通过以上任何一种方式可以实现的功能是，从安卓手机端提交数据到服务器端，服务器端进行判断，并返回相应的结果。三种方式各有利弊，实现效果相同，在实际的使用过程中可以根据本身的需要进行选择。