android 之post,get方式请求数据

须知少年凌云志，曾许人间第一流。这篇文章主要讲述android 之post,get方式请求数据相关的知识，希望能为你提供帮助。
【android 之post,get方式请求数据】get方式和post方式的区别：
1.请求的URL地址不同：
post："http://xx:8080//servlet/LoginServlet"
get：http://xxx:8080//servlet/LoginServlet?username=root& pwd=123
2.请求头不同：
****post方式多了几个请求头：Content-Length , Cache-Control , Origin
openConnection.setRequestProperty("Content-Length", body.length()+"");
openConnection.setRequestProperty("Cache-Control", "max-age=0");
openConnection.setRequestProperty("Origin", "http://192.168.13.83:8080");
****post方式还多了请求的内容：username=root& pwd=123
//设置UrlConnection可以写请求的内容
openConnection.setDoOutput(true);
//获取一个outputstream，并将内容写入该流
openConnection.getOutputStream().write(body.getBytes());
3.请求时携带的内容大小不同
get:1k
post:理论无限制

登录的布局文件

< ?xml version="1.0" encoding="utf-8"?> < LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" tools:context="com.example.yb.myapplication.MainActivity"> < EditText android:layout_width="fill_parent" android:layout_height="wrap_content" android:id="@+id/input_username" android:hint="@string/input_username"/> < EditText android:layout_marginTop="10dp" android:layout_marginBottom="10dp" android:inputType="textPassword" android:layout_width="fill_parent" android:layout_height="wrap_content" android:id="@+id/input_password" android:hint="@string/input_password"/> < RelativeLayout android:layout_width="fill_parent" android:layout_height="wrap_content"> < CheckBox android:layout_marginLeft="30dp" android:layout_centerVertical="true" android:layout_alignParentLeft="true" android:layout_width="wrap_content" android:layout_height="wrap_content" android:id="@+id/cb_rem" android:text="@string/reme_password"/> < Button android:layout_marginRight="30dp" android:paddingLeft="10dp" android:paddingRight="10dp" android:layout_alignParentRight="true" android:layout_width="wrap_content" android:layout_height="wrap_content" android:id="@+id/bt_login" android:text="@string/bt_login"/> < /RelativeLayout> < /LinearLayout>

登录的Activity代码

private EditText et_username; private EditText et_password; private CheckBox cb_rem; private Button bt_login; private Context mcontext; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_get_post); et_username = (EditText) findViewById(R.id.input_username); et_password = (EditText) findViewById(R.id.input_password); cb_rem = (CheckBox) findViewById(R.id.cb_rem); bt_login = (Button) findViewById(R.id.bt_login); bt_login.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { login(); } }); //界面加载完回显密码和用户名,读取文件，回显，用户名和密码的封装可以是：数组封装，Map封装，bean封装, /* Map< String, String> map = UserInfoUtil.getUserInfo(mcontext); if (map != null) { String username = map.get("username"); String password = map.get("password"); et_username.setText(username); et_password.setText(password); cb_rem.setChecked(true); }*/}public void login() {final String username = et_username.getText().toString().trim(); final String password = et_password.getText().toString().trim(); final boolean isRem = cb_rem.isChecked(); //判断是否密码或者用户名为空 if (TextUtils.isEmpty(username) || TextUtils.isEmpty(password)) { Toast.makeText(this, "用户名和密码不能为空", Toast.LENGTH_SHORT).show(); return; }//子线程操作，子线程不能做更新U I new Thread(new Runnable() { @Override public void run() { //get方法登录是否成功 // final boolean b = requestNetForGetLogin(username, password); final boolean b = requestNetForPOSTLogin(username, password); System.out.println("=====================是否登录成功：" + b); runOnUiThread(new Runnable() {//直接用acitivty类的runOnUiThread(runnable run)方法,可以在子线程中更新UI @Override public void run() { //运行在主线程里了 if (b) { //判断是否记住密码,要保存到本地，封装成方法 if (isRem) { //保存用户名和密码 boolean result = UserInfoUtil.saveUserInfo(mcontext, username, password); if (result) { Toast.makeText(getApplicationContext(), "用户名和密码保存成功", Toast.LENGTH_SHORT).show(); } else { Toast.makeText(getApplicationContext(), "用户名和密码保存失败", Toast.LENGTH_SHORT).show(); } } else { Toast.makeText(getApplicationContext(), "登录成功", Toast.LENGTH_SHORT).show(); } } else { Toast.makeText(getApplicationContext(), "登录失败", Toast.LENGTH_SHORT).show(); } } }); } }).start(); //请求服务器 }//get方式登录 private boolean requestNetForGetLogin(String username, String password) { //urlConnection请求服务器，验证 try { //1：url对象 URL url = new URL("http://192.168.1.100:8081/servlet/LoginServlet?username=" + username + "& pwd=" + password + ""); //2; url.openconnection HttpURLConnection conn = (HttpURLConnection) url.openConnection(); //3 conn.setRequestMethod("GET"); conn.setConnectTimeout(10 * 1000); //4 int code = conn.getResponseCode(); if (code == 200) { InputStream inputStream = conn.getInputStream(); String result = StreamUtil.stremToString(inputStream); System.out.println("=====================服务器返回的信息：：" + result); if (result.contains("success")) { return true; } } } catch (Exception e) { e.printStackTrace(); } return false; }//post方式登录 private boolean requestNetForPOSTLogin(String username, String password) { //urlConnection请求服务器，验证 try { //1：url对象 URL url = new URL("http://192.168.1.100:8081//servlet/LoginServlet"); //2; url.openconnection HttpURLConnection conn = (HttpURLConnection) url.openConnection(); //3设置请求参数 conn.setRequestMethod("POST"); conn.setConnectTimeout(10 * 1000); //请求头的信息 String body="username="+username+"& pwd="+password; conn.setRequestProperty("Content-Length", String.valueOf(body.length())); conn.setRequestProperty("Cache-Control","max-age=0"); conn.setRequestProperty("Origin","http://192.168.1.100:8081"); //设置conn可以写请求的内容 conn.setDoOutput(true); conn.getOutputStream().write(body.getBytes()); //4响应码 int code = conn.getResponseCode(); if (code == 200) { InputStream inputStream = conn.getInputStream(); String result = StreamUtil.stremToString(inputStream); System.out.println("=====================服务器返回的信息：：" + result); if (result.contains("success")) { return true; } } } catch (Exception e) { e.printStackTrace(); } return false; }

新建一个工具包Util, 新建一个类UserInfoUtil

public class UserInfoUtil { public static boolean saveUserInfo(Context context, String username, String password) { //需要使用shrare10.sharedPreference的使用 try {//1使用Context创建一个SharePerference对象 SharedPreferences sharedPreferences = context.getSharedPreferences("userinfo.txt", Context.MODE_PRIVATE); //2SharePerference对象得到Editor对象 Editor edit = sharedPreferences.edit(); //3往Editor对象里面添加数据 edit.putString("username",username); edit.putString("password",password); //4提交Editor对象 edit.commit(); return true; } catch (Exception e) { e.printStackTrace(); } return false; }//用户名和密码的封装可以是：数组封装，Map封装，bean封装,这里采用map封装 public static Map< String, String> getUserInfo(Context context) { try { //1 使用Context创建一个SharePerference对象 SharedPreferences sharedPreferences = context.getSharedPreferences("userinfo.txt", Context.MODE_PRIVATE); //2SharePerference对象获取存放的数据 String username = sharedPreferences.getString("username", ""); String password = sharedPreferences.getString("password", ""); HashMap< String, String> hashMap = new HashMap< String, String> (); hashMap.put("username", username); hashMap.put("password", password); return hashMap; } catch (Exception e) { e.printStackTrace(); } return null; }}

新建工具类StreamUtil,把获取的读取流转为String返回

public class StreamUtil { /** * 获取的读取流转为String返回 * * @param inputStream */ public static String stremToString(InputStream in) { String result=""; try { //创建一个字节数组写入流 ByteArrayOutputStream out=new ByteArrayOutputStream(); byte[] buffer=new byte[1024]; int length=0; while((length=in.read(buffer))!=-1){//如果返回-1 则表示数据读取完成了。 out.write(buffer,0,length); //写入数据 out.flush(); } result=out.toString(); //写入流转为字符串 out.close(); } catch (Exception e) { e.printStackTrace(); } return result; } }