第四章Servlet处理表单数据

JavaWeb开发天津师范大学刘洋第四章Servlet处理表单数据HTML表单Servlet接收HTML表单信息JSValidation验证框架FCKeditor更多参考信息HTML表单客户通过浏览器可以发送给Web服务器的请求一共有7种，“POST、GET、PUT、DELETE、OPTIONS、HEAD和TRACE”,但是在实际的Web编程中，我们只需要关注“POST”和“GET”请求，而其它的5种请求极少使用。POST请求是通过HTML中表单（Form）进行发送的，表单中包括了不同形式的输入组件Inputtext、Inputpassword、Inputradio、Inputcheckbox、Select单选、Select多选、Textarea

Submit按钮、Reset按钮HTML表单

Form标记使用的基本语法如下。<formmethod="post"action="/servlet/addMessage"></form>HTML表单Inputtext<formmethod="post“action="/servlet/login">用户名：<inputtype="text"name="username"size="16"maxlength="8"value="Liuwei"></form>HTML表单

Inputpassword<formmethod="post"action="/servlet/login">密码：<inputtype="password"name="password"size="20"maxlength="8"></form>HTML表单

Inputradio<formmethod="post"action="/servlet/login">请选择您的性别：<inputname="gender"type="radio"value="male"checked>男<inputname="gender"type="radio"value="female">女</form>HTML表单

Inputcheckbox<formmethod="post"action="/servlet/login">请选择您的兴趣：<inputname="interest"type="checkbox"value="movie">看电影<inputname="interest"type="checkbox"value="music">听音乐<inputname="interest"type="checkbox"value="tv">看电视<inputname="interest"type="checkbox"value="sing">唱歌</form>HTML表单

Select单选<formmethod="post"action="/servlet/login">请选择您的出生地：<selectname="city"><optionvalue="Beijing">北京</option><optionvalue="Tianjin">天津</option><optionvalue="Shanghai">上海</option><optionvalue="Chongqing"selected>重庆</option><optionvalue="etc">其它</option></select></form>HTML表单

Select多选<formmethod="post"action="/servlet/login">请选择您的兴趣：<selectname="interest"multiplesize="5"><optionvalue="movie">看电影</option><optionvalue="music">听音乐</option><optionvalue="tv">看电视</option><optionvalue="sing">唱歌</option></select></form>HTML表单

Textarea<formmethod="post"action="/servlet/guestbook">留言内容：<textareaname="comment"rows="10"cols="40">大家好</textarea></form>HTML表单

Submit按钮<formmethod="post"action="/servlet/login"><inputtype="submit"name="submit"value="确定"></form>HTML表单

Reset按钮<formmethod="post"action="/servlet/login">用户名：<inputname="username"size="16"maxlength="16"><inputtype="reset"value="重新输入"></form>Servlet接收HTML表单信息publicvoiddoGet(HttpServletRequestrequest,HttpServletResponseresponse) throwsServletException,IOException{

response.setContentType("text/html;charset=utf-8");

PrintWriterout=response.getWriter(); … out.println("<formmethod=\"post\"action=\""+request.getContextPath() +"/servlet/loginForm\">"); … out.println("用户名:</td><td>"); out.println("<inputtype=\"text\"name=\"username\"size=\"20\">"); out.println("</td></tr><tr><td>"); out.println("密码:</td><td>"); out.println("<inputtype=\"password\"name=\"password\"size=\"20\">"); … out.println("<td><inputtype=\"submit\"value=\"登录\"></td></tr>"); …

out.flush(); out.close(); }Servlet接收HTML表单信息publicvoiddoPost(HttpServletRequestrequest,HttpServletResponseresponse) throwsServletException,IOException{ response.setContentType("text/html;charset=utf-8"); …request.setCharacterEncoding("utf-8");…

Stringusername=request.getParameter("username"); Stringpassword=request.getParameter("password");

if(username==null||username.length()==0||password==null ||password.length()==0){ out.println("<h2>输入用户名和密码不正确！</h2>"); out.println("<br><ahref=\""+request.getContextPath() +"/servlet/loginForm\">请重新登录</A>"); }else{ out.println("<h2>用户输入信息：</h2>"); out.println("<strong>用户名："+username+"</strong><br>"); out.println("<strong>密码"+password+"</strong><br>"); } … }解决表单中文参数乱码HTML表单增加JavaScript验证

<formname="form1"action="/webproject2/servlet/login"method="post"onsubmit="returnvalidate(this)"><tableborder="0"><tr><td>用户名：</td><td><inputtype="text"name="username"></td></tr><tr><td>密码：<br></td><td><inputtype="password"name="password"></td></tr><tr><tdcolspan="2"align="center"><inputtype="submit"name="submit"value="登录"></td></tr></table></form>

HTML表单增加JavaScript验证<scriptlanguage="JavaScript"> functionvalidate(myform){ if(myform.username.value.length==0){ alert("请填写用户名！"); myform.username.focus(); returnfalse; } if(myform.password.value.length==0){ alert("请填写密码！"); myform.password.focus(); returnfalse; } returntrue; }</script>网络调查表html<formmethod="post"action="/webproject2/servlet/survey"><tableborder="0"><tr><tdalign="right">姓名：</td><tdcolspan="2"align="left"><inputtype="text"name="name"size="40"></td></tr>…<tr><td><inputtype="reset"value="reset"><inputtype="submit"value="submit"></td></tr></table></form>网络调查表/webproject2/servlet/surveypublicvoiddoPost(HttpServletRequestrequest,HttpServletResponseresponse) throwsServletException,IOException{ … out.println("<strong>用户名："+filter(request.getParameter("name")) +"</strong><br>"); out.println("<strong>email："+filter(request.getParameter("email")) +"</strong><br>"); out.println("<strong>年纪："+request.getParameter("age") +"</strong><br>"); out.println("<strong>编程时间："+request.getParameter("codetime") +"</strong><br>"); out.println("<strong>使用的操作系统：</strong>"); printValues(out,request.getParameterValues("os")); out.println("<strong>使用的编程语言：</strong>"); printValues(out,request.getParameterValues("language")); out.println("<strong>建议："+filter(request.getParameter("comment")) +"</strong><br>"); … }网络调查表filterpublicStringfilter(Stringinput){ if(input==null){ returnnull; } if(input.length()==0){ returninput; } input=input.replaceAll("&","&"); input=input.replaceAll("<","<"); input=input.replaceAll(">",">"); input=input.replaceAll(""," "); input=input.replaceAll("'","'"); input=input.replaceAll("\"","""); returninput.replaceAll("\n","<br>"); }网络调查表printValuespublicvoidprintValues(PrintWriterout,String[]values){ if(values==null||values.length==0){ return; } out.println("<ul>"); for(inti=0;i<values.length;i++){ out.println("<li>"+values[i]+"</li>"); } out.println("</ul>"); }JSValidation验证框架JSValidation验证框架的官方网址为：/projects/jsvalidation下载JSValidationJSValidation验证框架支持13种验证规则。输入内容非空输入数值必须为整数输入数值必须为双精度浮点数输入字符必须为普通英文字符（字母，数字，下划线）输入字符必须为中文字符输入的内容是否为Email格式输入内容最大长度输入内容最小长度输入的内容是否为日期格式（yyyy-mm-dd）自定义的正则表达式输入数值的整数范围（大于某数而小于某数）输入数值的双精度数范围输入内容必须与某个域的值相同JSValidation验证框架

validation-config.xml解释<validation-configlang="auto"> <formid="form1"show-error="error"show-type="all"> <fieldname="name"display-name="用户名"onfail=""> <dependname="required"/> <dependname="commonChar"/> <dependname="minLength"param0="3"/> <dependname="maxLength"param0="20"/> </field> <fieldname="email"display-name="email邮箱"> <dependname="required"/> <dependname="email"/> </field> <fieldname="age"display-name="年纪"> <dependname="required"/> </field><fieldname="codetime"display-name="编程时间"> <dependname="required"/> </field><fieldname="os"display-name="使用的操作系统"> <dependname="required"/> </field> <fieldname="language"display-name="使用的编程语言"> <dependname="required"/> </field> <fieldname="comments"display-name="建议"> <dependname="required"/> </field> </form></validation-config>…<head><title>潜在用户网络调查</title><metahttp-equiv