所有成功人士都有目标。如果一个人不知道他想去哪里，不知道他想成为什么样的人、想做什么样的事，他就不会成功。
下面我们开始建立留言的页面！ <%@page import ="java.util.*" import ="java.text.*" import="java.sql.*" import ="java.io.*" import ="java.lang.*" contentType="text/html; charset=gb2312" %> <% class CommentError// throws java.lang.NullPointerException { public String Username="",Sex="",Address="",Postal="",Oicq="",Icq="",Tel="",Comment=""; public boolean NoError=true;//false; public int ErrorCount=0; private boolean IsNumber(String s1) {} public String font (String se) {} public String Comment_Er(String se) {} public void Username (String se) {} public void Sex (String se) {} public void Address (String se) {} public void Comment (String se) {} public void Tel (String se) {} public void Postal (String se) {} public void Oicq (String se) {} public void Icq (String se) {} } class FormatComment { public String Replace(String source, String oldString, String newString) {} public String formatint(String se) {} public String fromatcomment(String se) {} public String toHtmlInput(String str) {} public String toHtml(String str) {} public String toSql(String str) {}//转换为可以加入Myqal的格式 } %> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=gb2312"> <meta name="GENERATOR" content="Microsoft FrontPage 4.0"> <meta name="ProgId" content="FrontPage.Editor.Document"> <title>使用MYsql数据库</title> </head> <body> <p align="center"><center><font style="COLOR: blue; FONT-FAMILY: 方正舒体,华文行楷,隶书,宋体; FONT-SIZE: 16pt">萍慧jsp留言薄</font></center></p> <p align="center"> <%! String username,sex,address,post,oicq,icq,telnumber,comment,email,url.urltitle; %> <% try{ username=request.getParameter("name"); }catch (NullPointerException e){ username="";} try{ comment=request.getParameter("comment"); }catch (NullPointerException e){ comment="";} try{ sex=request.getParameter("sex"); }catch (NullPointerException e){ sex="";} try{ address=request.getParameter("address"); }catch (NullPointerException e){ address="";} try{ post=request.getParameter("postal"); }catch (NullPointerException e){ post="";} try{ oicq=request.getParameter("oicq"); }catch (NullPointerException e){ oicq="";} try{ icq=request.getParameter("icq"); }catch (NullPointerException e){ icq="";} try{ telnumber=request.getParameter("telphone"); }catch (NullPointerException e) { telnumber= ""; } try{ email=request.getParameter("email"); }catch (NullPointerException e) { email= ""; } try{ url=request.getParameter("url"); }catch (NullPointerException e) { url= ""; } try{ urltitle=request.getParameter("urltitle"); }catch (NullPointerException e) { urltitle= ""; } String ip=request.getRemoteAddr();//得到IP地址 String time=(new SimpleDateFormat ("yyyy-MM-dd hh:mm:ss", Locale.US )).format(new java.util.Date()); String userid=""; String MyQuery=""; 此处我调用了一个对留言进行合法检验的类 CommentError testcomment= new CommentError(); testcomment.Username(username); testcomment.Postal (post); testcomment.Sex(sex); testcomment.Address(address); testcomment.Tel(telnumber); testcomment.Comment(comment); testcomment.Oicq(oicq); testcomment.Icq(icq); if (testcomment.NoError) //留言中没有错误,写数据库 try {//写数据库成功java.sql.Connection sqlConn; //数据库连接对象 java.sql.Statement sqlStmt; //语句对象 java.sql.ResultSet sqlRst; //结果集对象 //登记JDBC驱动对象 Class.forName ("org.gjt.mm.mysql.Driver").newInstance (); //连接数据库 sqlConn= java.sql.DriverManager.getConnection ("jdbc:mysql://localhost/pinghui","test",""); //创建语句对象 sqlStmt=sqlConn.createStatement (java.sql.ResultSet.TYPE_SCROLL_INSENSITIVE,java.sql.ResultSet.CONCUR_READ_ONLY); //执行Sql语句 此处调用了一个对留言进行处理的类，是留言能被Mysql承认, FormatComment FC= new FormatComment();oicq=FC.formatint(oicq);icq=FC.formatint(icq);post=FC.formatint(post);telnumber=FC.formatint(telnumber);username=FC.toSql(username);comment=FC.toSql(comment);MyQuery="insert into comment (username,sex,address,ip,post,oicq,icq,telnumber,comment,time,url,email) values ('"+username+"','"+sex+"','"+address+"','"+ip+"',"+post+","+oicq+","+icq+",'"+telnumber+"','"+comment+"',now(),'"+url+"','"+email+"');"; sqlRst=sqlStmt.executeQuery (MyQuery); //向数据库中加入数据 sqlRst.close();//关闭结果集对象 sqlStmt.close ();//关闭语句对象 sqlConn.close(); //关闭数据库连接 out.print (time); %> <font size="5" face="华文行楷">留言成功,谢谢!</font> <table border="0" cellpadding="0" cellspacing="0" width="100%"> <tbody> <tr> <td width="25%">昵称：<%=username%></td> <td width="25%">性别：<%=sex%></td> <td colspan="2" width="50%">地址：<%=address %></td> </tr> <tr> <td width="25%">电话：<%=telnumber%></td> <td width="25%">邮编：<%=post%></td> <td width="25%">OICQ：<%=oicq%></td> <td width="25%">ICQ：<%=icq%></td> </tr> <tr> <td colspan="2" width="50%">Email：<a rel="nofollow noopener noreferrer" href="mailto:" title="写信给留言者"></a></td> <td colspan="2" width="50%">网址：<a href target="_blank"></a></td> </tr> <tr> <td colspan="4"><font style="COLOR: green; LINE-HEIGHT: 150%">留言：</font><%=comment%><font style="COLOR: green; LINE-HEIGHT: 150%"><br> -</font><%=time %><font style="COLOR: green; LINE-HEIGHT: 150%">（来自</font><%=ip %><font style="COLOR: green; LINE-HEIGHT: 150%">）</font></td> </tr> </tbody> </table> <hr color="#0080c0" noshade size="1" width="100%"> <% } catch (SQLException e) //写数据库失败 { out.print ("<font color=red>留言失败</font>"); out.print (MyQuery); out.print (userid); } else { out.print ("<font color=red>总共有"+testcomment.ErrorCount+"条错误数据,请修改!</font>"); %> <script language="JavaScript"> <!-- function test_comments(theForm) { if (theForm.name.value == "") {alert("姓名不能为空！：-）"); theForm.name.focus(); return (false); } if (theForm.name.value.length > 12) { alert("姓名太长，不能多于12个字符(既六个汉字)！"); theForm.name.focus(); return (false); } if (theForm.address.value.length > 40) { alert("地址太长，不能多于40个字符(20个汉字)！"); theForm.name.focus(); return (false); } if (theForm.comment.value == "") { alert("抱歉，留言不能为空!你必须输入留言"); theForm.comment.focus(); return (false); } if (theForm.comment.value.length > 1000) { alert("抱歉，你的留言太长，最多为1000个字符！"); theForm.comment.focus(); return (false); } return (true); } --> <table> <tr> <td> <table cellspacing="0" cellpadding="0"> <tr> <td><!--表单开始--> <form action="addmysql.jsp" method="POST" name="all_comments" onsubmit="javascript：return (test_comments(this))"> <table border="0" width="100%" cellspacing="0" cellpadding="0"> <tr> <td width="60%">昵称：<input name="name" size="20" value="<%if (username != null) out.print (username);%>"><%=testcomment.Comment_Er("username")%></td> <td nowrap width="40%">性别：<select name="sex" size="1"> <option selected value="男" <%if(sex=="男") out.print ("select"); %>>男</option> <option value="女" <%if(sex=="女") out.print ("select"); %>>女</option> <option value="保密" <%if(sex=="保密") out.print ("select"); %>>保密</option> </select><%=testcomment.Comment_Er("sex")%></td> </tr> <tr> <td colspan="2">地址：<input name="address" size="40" value="<%if (address!=null) out.print(address);%>"><%=testcomment.Comment_Er("address")%></td> </tr> <tr> <td>电话：<input name="telphone" size="15" value="<%if(telnumber!=null)out.print(telnumber);%>"><%=testcomment.Comment_Er("tel")%></td> <td>邮编：<input name="postal" size="6" value="<%if(post!=null) out.print(post);%>"><%=testcomment.Comment_Er("postal")%></td> </tr> <tr> <td>OICQ：<input name="oicq" size="10" value="<%if(oicq!=null) out.print (oicq);%>"><%=testcomment.Comment_Er("oicq")%></td> <td>ICQ：<input name="icq" size="15" value="<%if(icq!=null)out.print(icq);%>"><%=testcomment.Comment_Er("icq")%></td> </tr> <tr> <td colspan="2">Email：<input name="email" size="25" value="<%if(email!=null) out.print(email);%>"><%//=testcomment.Comment_Er("")%></td> </tr> <tr> <td colspan="2">网址：<input name="url" size="40" value="<%if(url!=null)out.print(url);%>"><%//=testcomment.Comment_Er("")%></td> </tr> <tr> <td colspan="2"><textarea cols="80" name="comment" rows="10" wrap="physical"><%if (comment!=null)out.print (comment);%></textarea> <tr> <td align="right"><input name="put_submit" type="submit" value="确定" ?></td> <td align="left"><input name="r" type="reset" value="重置"></td> </tr> </table> </form> <!--提交表单结束--> </td> <td><%=testcomment.Comment_Er("comment")%>请注意：你所输入的内容中，昵称和留言为必须输入的项目！<br> 不支持html标志</td> </tr> </table> </td> </tr> </table> <% } %> </body> 本文如何如何使用JSP+MySQL创建留言本(三)到此结束。朋友用心交，父母拿命孝。小编再次感谢大家对我们的支持！