表单处理的方案与注意事项（servlet）

摘要
表单是后端程序员用的与接触最多的，我这里例举了常用处理办法，与注意事项

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sevlet处理代码

package myform;

import java.io.IOException;
import java.io.PrintWriter;
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 resvrcData extends HttpServlet {

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp)
            throws ServletException, IOException {
        // TODO Auto-generated method stub
        // super.doGet(req, resp);
        doPost(req, resp);
    }
    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp)
            throws ServletException, IOException {
        // TODO Auto-generated method stub
        // super.doPost(req, resp);
        resp.setContentType("text/html;charset=UTF-8");
        resp.setCharacterEncoding("UTF-8");
        PrintWriter writer = resp.getWriter();
        Enumeration<String> names = req.getParameterNames();
        String parameter = req.getParameter("r");
        //System.out.println(parameter);
        while (names.hasMoreElements()) {
            //writer.write(names.nextElement());
            writer.write(req.getParameter(names.nextElement()));
        }
        writer.close();
    }

}

注意
我看了类似网上代码，忽略写servlet配置文件 在html写数据到servlet是会报404 错误代码的 所以必须配置

radiobox

checkbox

select

        <center>
            <!-- name的值相同才能做相同绑定 multiple="multiple"-->
            <form method="post" action="/SessionTchCookies/myform/resvrcData.do">
            <select name="select1" >
            <option value="o1">1</option>
            <option value="o2">2</option>
            <option value="o3">3</option>
            <option value="o4">4</option>           
            </select>
             <input type="submit" value="提交"/>
            </form>
        </center>

包含optgroup表单的属性设置

<form method="post" action="/SessionTchCookies/myform/resvrcData.do">
            <br>
            <br> <select name="test" id="select">
                <ins>ss</ins>
                <optgroup label="num">
                    <option value="11" disabled>1</option>
                    <option value="22" selected>2</option>
                    <option value="33">3</option>
                    <option value="44" label="word">4</option>
                </optgroup>
                <optgroup label="word">
                    <option>a</option>
                    <option>b</option>
                    <option>c</option>
                    <option>d</option>
                </optgroup>
                <optgroup label="汉字" disabled>
                    <option value="一个">一</option>
                    <option value="二个">二</option>
                    <option value="三个">三</option>
                    <option value="四个">四</option>
                </optgroup>
            </select> <input type="submit">