Android網路請求

標籤：bsp   while   inpu   net   pos   stream   url   date   creat   

HTTP請求與響應

HTTP請求包結構

例：

POST /meme.php/home/user/login HTTP/1.1    Host: 114.215.86.90    Cache-Control: no-cache    Postman-Token: bd243d6b-da03-902f-0a2c-8e9377f6f6ed    Content-Type: application/x-www-form-urlencoded    tel=13637829200&password=123456

HTTP響應包結構

例：

HTTP/1.1 200 OK    Date: Sat, 02 Jan 2016 13:20:55 GMT    Server: Apache/2.4.6 (CentOS) PHP/5.6.14    X-Powered-By: PHP/5.6.14    Content-Length: 78    Keep-Alive: timeout=5, max=100    Connection: Keep-Alive    Content-Type: application/json; charset=utf-8    {"status":202,"info":"\u6b64\u7528\u6237\u4e0d\u5b58\u5728\uff01","data":null}

Http請求方式

常用的是Post和Get

Get方式

在url中填寫參數：http://xxxx.xx.com/xx.php?params1=value1&params2=value2

Post方式

參數是經過編碼放在請求體中的。編碼包括x-www-form-urlencoded 與 form-data。

 x-www-form-urlencoded的編碼方式是這樣： tel=13637829200&password=123456

 form-data的編碼方式是這樣：

----WebKitFormBoundary7MA4YWxkTrZu0gW  Content-Disposition: form-data; name="tel"  13637829200  ----WebKitFormBoundary7MA4YWxkTrZu0gW  Content-Disposition: form-data; name="password"  123456  ----WebKitFormBoundary7MA4YWxkTrZu0gW

x-www-form-urlencoded只能傳索引值對，form-data可以傳二進位

HttpClient & HttpURLConnection

HttpClient已被廢棄

HttpURLConnection的用法

public class NetUtils {        public static String post(String url, String content) {            HttpURLConnection conn = null;            try {                // 建立一個URL對象                URL mURL = new URL(url);                // 調用URL的openConnection()方法,擷取HttpURLConnection對象                conn = (HttpURLConnection) mURL.openConnection();                conn.setRequestMethod("POST");// 佈建要求方法為post                conn.setReadTimeout(5000);// 設定讀取逾時為5秒                conn.setConnectTimeout(10000);// 設定串連網路逾時為10秒                conn.setDoOutput(true);// 設定此方法,允許向伺服器輸出內容                // post請求的參數                String data = content;                // 獲得一個輸出資料流,向伺服器寫資料,預設情況下,系統不允許向伺服器輸出內容                OutputStream out = conn.getOutputStream();// 獲得一個輸出資料流,向伺服器寫資料                out.write(data.getBytes());                out.flush();                out.close();                int responseCode = conn.getResponseCode();// 調用此方法就不必再使用conn.connect()方法                if (responseCode == 200) {                    InputStream is = conn.getInputStream();                    String response = getStringFromInputStream(is);                    return response;                } else {                    throw new NetworkErrorException("response status is "+responseCode);                }            } catch (Exception e) {                e.printStackTrace();            } finally {                if (conn != null) {                    conn.disconnect();// 關閉串連                }            }            return null;        }        public static String get(String url) {            HttpURLConnection conn = null;            try {                // 利用string url構建URL對象                URL mURL = new URL(url);                conn = (HttpURLConnection) mURL.openConnection();                conn.setRequestMethod("GET");                conn.setReadTimeout(5000);                conn.setConnectTimeout(10000);                int responseCode = conn.getResponseCode();                if (responseCode == 200) {                    InputStream is = conn.getInputStream();                    String response = getStringFromInputStream(is);                    return response;                } else {                    throw new NetworkErrorException("response status is "+responseCode);                }            } catch (Exception e) {                e.printStackTrace();            } finally {                if (conn != null) {                    conn.disconnect();                }            }            return null;        }        private static String getStringFromInputStream(InputStream is)                throws IOException {            ByteArrayOutputStream os = new ByteArrayOutputStream();            // 模板代碼 必須熟練            byte[] buffer = new byte[1024];            int len = -1;            while ((len = is.read(buffer)) != -1) {                os.write(buffer, 0, len);            }            is.close();            String state = os.toString();// 把流中的資料轉換成字串,採用的編碼是utf-8(模擬器預設編碼)            os.close();            return state;        }    }

添加網路許可權：<uses-permission android:name="android.permission.INTERNET"/>

 

同步&非同步

非同步方式：

//在主線程new的Handler，就會在主線程進行後續處理。    private Handler handler = new Handler();    private TextView textView;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        textView = (TextView) findViewById(R.id.text);        new Thread(new Runnable() {            @Override            public void run() {                    //從網路擷取資料                final String response = NetUtils.get("http://www.baidu.com");                    //向Handler發送處理操作                handler.post(new Runnable() {                    @Override                    public void run() {                            //在UI線程更新UI                        textView.setText(response);                    }                });            }        }).start();    }

 

參考文獻：http://www.jianshu.com/p/3141d4e46240

 

Android網路請求