Request--获得请求体数据，获得请求参数通用方式演示

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Request–获得请求体数据

package cn.itcast.web.request;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.BufferedReader;
import java.io.IOException;

@WebServlet("/RequestDemo5")
public class RequestDemo5 extends HttpServlet {
     
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
     
        //获取消息请求体

        //1.获取字符串
        BufferedReader reader = request.getReader();
        //2.读取数据
        String line=null;
        while ((line=reader.readLine())!=null){
     
            System.out.println(line);
        }

    }

    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
     

    }
}

  <form action="/RequestDemo5" method="post">
    <input type="text" placeholder="UserName" name="username"><br>
    <input type="text" placeholder="PassWord" name="password"><br>
    <input type="submit" value="regist">
  </form>

username=root&password=123

Request–获得请求参数通用方式介绍

Request–获得请求参数通用方式演示

• 简化相同代码
  
  
  
  

        Enumeration<String> parameterNames = request.getParameterNames();
        while (parameterNames.hasMoreElements()){
     
            String s = parameterNames.nextElement();

            String[] parameterValues = request.getParameterValues(s);
            for (String parameterValue : parameterValues) {
     
                System.out.println(s+"="+parameterValue);
            }

        }

       Map<String, String[]> parameterMap = request.getParameterMap();

        Set<String> strings = parameterMap.keySet();
        for (String string : strings) {
     

            String[] strings1 = parameterMap.get(string);

            for (String s : strings1) {
     
                System.out.println(string + "=" + s);
            }


        }