JavaWeb学习-Servlet系列-21-HttpServletRequest获取请求正文方法介绍（二）

迈不过友情╰ 2022-01-31 00:57 193阅读 0赞

继续来做HttpServletRequest获取请求正文的方法练习，本篇就学习一个方法getParameterNames()，也就是获取表单中所有name属性的值的一个方法，例如我们注册表单中的userName,pwd,hobby等。

1.register.html内容

<?xml version="1.0" encoding="UTF-8" ?>
    <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
    <html xmlns="http://www.w3.org/1999/xhtml">
    <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
    <title>Register Page</title>
    </head>
    <body>
    	<form action="/Servlet01/demo4" method="post">
    		用户名：<input type="text" name="userName" /><br/>
    		密码：<input type="password" name="pwd" /><br/>
    		性别：<input type="radio" name="gender" value="男" checked="checked"/>男
    			<input type="radio" name="gender" value="女" />女<br/>
    		爱好：
    		<input type="checkbox" name="hobby" value="篮球" />篮球
    		<input type="checkbox" name="hobby" value="唱歌" />唱歌
    		<input type="checkbox" name="hobby" value="编码" />编码<br/>
    		所在城市：
    		<select name="city">
    			<option>---请选择---</option>
    			<option value="BJ">北京</option>
    			<option value="SH">上海</option>
    			<option value="gz">广州</option>
    		</select><br/>
    		<input type="submit" value="注册"/>
    	</form>
    </body>
    </html>

2.ServletDemo4.java

package com.anthony.servlet;
    
    import java.io.IOException;
    import java.util.Enumeration;
    
    import javax.servlet.ServletException;
    import javax.servlet.http.HttpServlet;
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    
    
    public class ServletDemo4 extends HttpServlet {
    
    	@Override
    	protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
    		req.setCharacterEncoding("UTF-8");
    		//获取表单中全部name的值
    		Enumeration<String> names = req.getParameterNames();
    		while(names.hasMoreElements()) {
    			String name = names.nextElement();
    			
    			//考虑到hobby下有多个值
    			String[] values = req.getParameterValues(name);
    			for (int i = 0; values != null && i < values.length; i++) {
    				System.out.println(name +"\t"+ values[i]);
    			}
    		}
    	}
    
    
    	@Override
    	protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
    		doGet(req, resp);
    	}
    	
    }

测试结果

userName	AnthonyLiu
    pwd	dfewfewf
    gender	男
    hobby	篮球
    hobby	编码
    city	SH