（1）编写程序实现写留言板内容的功能。 编写一个JSP页面writefile.jsp，该页面提供一个表单，用户可以通过表单输入留言标题和内容，提交留言跳转到WriteFileContent.jsp页面。WriteFileContent.jsp页面调用write_file.tag文件，把留言板信息写入C:/Students/save.txt文件中。 write_file.tag文件功能：读出C:/Students/save.txt文件内容，与所提交留言合并，写入该文件中。 （2）编写程序实现读取留言板内容。 编写一个JSP页面readfile.jsp，调用read_file.tag文件，读出C:/Students/save.txt文件内容。 writefile.jsp(网页设计)
<%@ page language="java" contentType="text/html;charset=gb2312"%> <%@ taglib tagdir="/WEB-INF/tags" prefix="guan" %> <form action="../Writefilecontent.jsp" method=get name=form> <h2>留言板</h2> <p>留言者:<input type="text" name="theme" /><br> 内容：<textarea name="messa" rows="10" cols="36" ></textarea><br><br> <input type="submit" value="提交" name="sub" /> </form></body></html>WriteFileContent.jsp
<%@ page contentType="text/html;charset=gb2312"%> <%@taglib tagdir="/WEB-INF/tags" prefix="guan" %> <body > <form action="" method=get name=form> <% String bt=request.getParameter("theme"); String str=request.getParameter("messa"); if(bt==null) bt=""; if(str==null) str=""; byte b[]=bt.getBytes("iso-8859-1"); byte a[]=str.getBytes("iso-8859-1"); //汉字处理 bt=new String(b); str=new String(a); %> <BR><guan:Write_file bt="<%=bt %>" nr="<%=str %>"/> <br> <%=hnr %> <a href="../Readfile.jsp">查看留言 </a><br> <a href="..//Writefile.jsp"> 返回继续留言</a> </form></body></html>write_file.tag(需要手动在C盘新建save.txt)
<%@tag pageEncoding="gb2312" %> <%@tag import="java.io.*" %> <%@attribute name="nr" required="true" %> <%@attribute name="bt" required="true" %> <%@variable name-given="hnr" scope="AT_END" %> <% File dir=new File("C:/","Students"); File f=new File(dir,"save.txt"); StringBuffer mess=new StringBuffer(); String str; try{ FileReader in=new FileReader(f); BufferedReader bufferin=new BufferedReader(in); String temp; while((temp=bufferin.readLine())!=null){ mess.append(temp);} bufferin.close(); //读数据 in.close();} catch(IOException e){ jspContext.setAttribute("nr",mess); jspContext.setAttribute("bt",mess); } try{ FileWriter outfile=new FileWriter(f); BufferedWriter bufferout=new BufferedWriter(outfile); bufferout.write(mess+"#"+bt+":"+nr); bufferout.close(); outfile.close(); //写数据 jspContext.setAttribute("hnr","留言提交成功"); } catch(IOException e){ jspContext.setAttribute("hnr","留言提交失败"); } %>read_file.tag
<%@tag pageEncoding="gb2312" %> <%@tag import="java.io.*" %> <%@tag import="java.util.ArrayList" %> <%@tag import="java.util.List" %> <%@attribute name="dir" required="true" %> <%@attribute name="fileName" required="true" %> <%@variable name-given="result" variable-class="java.util.ArrayList" scope="AT_END" %> <%! public String readContent(File f) { StringBuffer str=new StringBuffer(); try{ FileReader in=new FileReader(f); //读出txt中的数据 BufferedReader bufferin=new BufferedReader(in); String temp; while((temp=bufferin.readLine())!=null){ str.append(temp);} bufferin.close(); in.close();} catch(IOException e){} return new String(str); } %> <% File f=new File(dir,fileName); String fileContent=readContent(f); ArrayList<String> list=new ArrayList<String>(); //返回给JSP页面的list对象 String regex="#"; String words[]=fileContent.split(regex); for(int i=0;i<words.length;i++){ list.add(words[i]); } jspContext.setAttribute("result",list); %>readfile.jsp
<%@ page contentType="text/html;charset=gb2312"%> <%@ taglib tagdir="/WEB-INF/tags" prefix="guan" %> <html><body > <guan:Read_file dir="C:/Students" fileName="save.txt"/> 留言内容：<br> <% for(int i=0;i<result.size();i++){ out.print(result.get(i)+"<hr height=10 color=red width=360 />"); } %> </form> </body> </html>运行界面
