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jsp初学者请教各位大侠
一个简单的管理员后台登陆login.jsp,jdk-6u10-rc2-bin-b32-windows-i586-p-12_sep_2008.exe和
apachetomcat.exe<%@ page contentType="text/html; charset=gb2312" language="java" import="java.sql.*" errorPage="" %>
<%@ page import="java.io.*" %>
<%@ page import="java.net.URLDecoder" %>
<% request.seCharacterEncoding("gb2312"); %>
<!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=gb2312" />
<title>后台登陆</title>
</head>
<BODY bgcolor="#FFFFFF" topmargin="0" leftmargin="0"> 
<FORM method="post" id="adminlogin" action="../../Job recruitment/checklogin.jsp" name="adminlogin" onSubmit="return check();">
  
  <DIV align="center">
    <TABLE width="90&percnt;" height="80&percnt;" border="0" cellpadding="0" cellspacing="0">
      <TBODY><TR>
        <TD>
          
          <DIV align="left">
            <TABLE cellspacing="0" cellpadding="0" width="372" align="center" border="0">
              <TBODY>
                <TR> 
                  <TD colspan="3"><IMG height="49" src="../../Job recruitment/admin/image/admin_03.gif" width="385"></TD>
                </TR>
                <TR> 
                  <TD valign="top" align="left" width="16" rowspan="2"><IMG height="204" src="../../Job recruitment/admin/image/admin_06.gif" width="16"></TD>
                  <TD height="175"> <TABLE cellspacing="0" cellpadding="0" width="348" border="0">
                      <TBODY>
                        <TR> 
                          <TD height="165"> <DIV align="center"> 
                            <CENTER>
                              <TABLE id="AutoNumber1" style="BORDER-COLLAPSE: collapse" bordercolor="#E1EFF7" height="107" cellspacing="0" cellpadding="0" width="255" border="1">
                                <TBODY>
                                  <TR> 
                                    <TD bgcolor="#F4F9FC"> 
                                      <TABLE width="100%" border="0" cellspacing="0" cellpadding="0">
                                        <TBODY><TR> 
                                          <TD width="122" height="30" align="right">用户名：</TD>
                                            <TD width="129" height="30">  <INPUT name="username" type="text" id="UserName5" style="BORDER-RIGHT: 1px solid; BORDER-TOP: 1px solid; BORDER-LEFT: 1px solid; WIDTH: 110px; BORDER-BOTTOM: 1px solid" maxlength="20" class="login"></TD>
                                          </TR>
                                        <TR> 
                                          <TD height="30" align="right">密　码：</TD>
                                            <TD height="30"> <INPUT name="password" type="password" id="Password3" maxlength="20" class="login" style="BORDER-RIGHT: 1px solid; BORDER-TOP: 1px solid; BORDER-LEFT: 1px solid; WIDTH: 110px; BORDER-BOTTOM: 1px solid"></TD>
                                          </TR>
                                        <TR> 
                                          <TD height="30" align="right"><FONT color="#000000">验证码：</FONT></TD>
          
                                          <TD height="30">  <INPUT name="code" type="text" class="kuan" id="code" size="7">
                                          &nbsp;</TD>
                                          </TR>
                                      </TBODY></TABLE>                                    </TD>
                                    </TR>
                                  </TBODY>
                                </TABLE>
                              </CENTER>
                            </DIV></TD>
                        </TR>
                        <TR> 
                          <TD valign="top" align="center" height="31"><input type="submit" name="Submit3" value=" submit" style="background-color: #E1EFF7" />                            &nbsp;&nbsp;&nbsp;&nbsp;
                            <INPUT type="reset" name="Submit2" value=" 重置 " style="background-color:#E1EFF7">                         </TD>
                        </TR>
                      </TBODY>
                    </TABLE></TD>
                  <TD valign="top" width="12" rowspan="2"><IMG height="204" src="../../Job recruitment/admin/image/admin_077.gif" width="12"></TD>
                </TR>
                <TR> 
                  <TD width="357" height="9"><IMG height="9" src="../../Job recruitment/admin/image/admin_14.gif" width="357"></TD>
                </TR>
            </TBODY></TABLE>
        </DIV></TD>
      </TR>
   <tr>
      <td colspan="2" align="center" valign="top" class="mainnews"><br />
      版权所有<br />
      Copyright 2009 NENU All rights reserved</td>
    </tr>
          </TBODY></TABLE>
  </DIV>
</FORM>
<%!
private String getInput(String arg) throws UnsupportedEncodingException{
if (arg == null){
return "";
}
//首先将URL编码字符串解码
String tempVar =URLDecoder.decode(arg,"utf-8");
if (tempVar == null){
tempVar =new String(tempVar.getBytes("ISO-8859-1"), "gb2312");
}
return tempVar;
}
%></BODY>
</html>                  <TD colspan="3"><IMG height="49" src="../../Job recruitment/admin/image/admin_03.gif" width="385"></TD>