android中Post方式發送HTTP請求

通過Post方式發送HTTP請求的代碼邏輯,代碼在Eclipse中實現

 

一.主要步驟

1.准備數據裝入mydata(一個字節數組)

2.建立連接,設置請求體

HttpURLConnection connection = (HttpURLConnection) url.openConnection(); 

connection.setConnectTimeout(3000);

connection.set...;　　　　　　//設置請求體

connection.connect;

3.通過連接輸出數據

OutputStream outputStream = connection.getOutputStream(); 

outputStream.write(mydata,0,mydata.length);

4.通過連接獲取服務器返回結果

connection.getInputStream()

 

二.demo 

import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.io.UnsupportedEncodingException; import java.net.HttpURLConnection; import java.net.MalformedURLException; import java.net.URL; import java.net.URLEncoder; import java.util.HashMap; import java.util.Map; public class HttpUtils { private static String PATH = "http://172.24.87.47:8088/myhttp/servlet/LoginAction"; private static URL url; public HttpUtils() {} static{ try { url = new URL(PATH); } catch (MalformedURLException e) {   e.printStackTrace(); } } 
　　

public static void main(String[] arsg){ Map<String, String> params = new HashMap<String, String>(); params.put("username", "lili"); params.put("password", "123"); String result = sendPostMessage(params,"utf-8"); System.out.println("result->"+result); }

 

/** * @param params 填寫的url的參數 * @param encode 字節編碼 * @return */ public static String sendPostMessage(Map<String, String> params,String encode){ StringBuffer buffer = new StringBuffer(); try {//把請求的主體寫入正文！！  if(params != null&&!params.isEmpty()){ //迭代器 
　　　　　　　　　 //Map.Entry 是Map中的一個接口，他的用途是表示一個映射項（里面有Key和Value）
　　　　　　　　　　　for(Map.Entry<String, String> entry : params.entrySet()){ buffer.append(entry.getKey()).append("="). append(URLEncoder.encode(entry.getValue(),encode)). append("&"); } } // System.out.println(buffer.toString()); //刪除最后一個字符&，多了一個;主體設置完畢  buffer.deleteCharAt(buffer.length()-1); byte[] mydata = buffer.toString().getBytes(); HttpURLConnection connection = (HttpURLConnection) url.openConnection(); connection.setConnectTimeout(3000); connection.setDoInput(true);//表示從服務器獲取數據  connection.setDoOutput(true);//表示向服務器寫數據   connection.setRequestMethod("POST"); //是否使用緩存  connection.setUseCaches(false); //表示設置請求體的類型是文本類型  connection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded"); connection.setRequestProperty("Content-Length", String.valueOf(mydata.length)); connection.connect(); //連接，不寫也可以。。？？有待了解 //獲得輸出流，向服務器輸出數據  OutputStream outputStream = connection.getOutputStream(); outputStream.write(mydata,0,mydata.length); //獲得服務器響應的結果和狀態碼  int responseCode = connection.getResponseCode(); if(responseCode == HttpURLConnection.HTTP_OK){ return changeInputeStream(connection.getInputStream(),encode); } } catch (UnsupportedEncodingException e) { // TODO Auto-generated catch block   e.printStackTrace(); } catch (IOException e) { // TODO Auto-generated catch block   e.printStackTrace(); } return ""; } /** * 將一個輸入流轉換成字符串 * @param inputStream * @param encode * @return */ private static String changeInputeStream(InputStream inputStream,String encode) { //通常叫做內存流，寫在內存中的  ByteArrayOutputStream outputStream = new ByteArrayOutputStream(); byte[] data = new byte[1024]; int len = 0; String result = ""; if(inputStream != null){ try { while((len = inputStream.read(data))!=-1){ data.toString(); outputStream.write(data, 0, len); } //result是在服務器端設置的doPost函數中的  result = new String(outputStream.toByteArray(),encode); outputStream.flush(); } catch (IOException e) { // TODO Auto-generated catch block   e.printStackTrace(); } } return result; }  }  

 參考文章:https://www.cnblogs.com/jycboy/p/post01.html 　　作者:超超boy