求解!jsp从表单获取的值为空!
一:
search.jsp
<%@ page language="java" import="java.util.*,java.sql.*" pageEncoding="gbk"%>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=GBK" />
<title>无标题文档</title>
</head>
<body>
<form id="form2" name="form2" method="post" action="adcheck.jsp">
<table width="76%" height="514" border="0" align="center">
<tr>
<td width="553" height="508">
<%
Connection con;
Statement smt=null;
ResultSet rs=null;
try{ Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
}
catch(ClassNotFoundException e)
{ out.print(e);
}
try { con=DriverManager.getConnection("jdbc:odbc:huojiang","",""); //注意数据源的名称,用户名和密码,ODBC连接
smt=con.createStatement();
}
catch(SQLException e)
{ out.print(e);
}
%>
<table width="100%" border="1" align="center" cellpadding="0" cellspacing="0" bordercolor="#999999" >
<tbody>
<tr bgcolor="#CCCCCC">
<td colspan="7" align="center" bgcolor="#FFFFFF"><font size="3" color="#ffffff"><b><font color="#000000">大学生获奖信息管理平台</font></b></font></td>
</tr>
<tr align="center">
<td colspan="7"><a href="add.jsp">发布信息</a> <a href="javascript:this.location.reload()">刷新</a> <a href="index.jsp">首页</a>
<div align="right"></div></td>
</tr>
<tr>
<td width="14%">竞赛项目</td>
<td width="14%">时间</td>
<td width="11%">获奖等级</td>
<td width="13%">获奖人</td>
<td width="12%">指导教师</td>
<td width="12%" height="20">备注</td>
<td width="24%" align="center"> </td>
</tr>
<%
//在这里测试为空
String s1=request.getParameter("keyword");
String s=request.getParameter( "style");
String sql=null;
if(s=="竞赛项目"){
sql= "select * from shijian where 竞赛项目 = ' "+s1+ " ' " ;
System.out.println(s1+s);
}
else{
}
rs = smt.executeQuery(sql);
while(rs.next())
{
int a=rs.getInt("ID"); //在access中rs.getString("字段名")不能多次被使用
%>
<tr>
<td><div align="left"><span class="text">●</span><a href="edit.jsp?ID=<%=a%>"><%=rs.getString("竞赛项目")%></a></div></td>
<td><%=rs.getString("时间")%></td>
<td><%=rs.getString("获奖等级")%></td>
<td><%=rs.getString("获奖人")%></td>
<td><%=rs.getString("指导教师")%></td>
<td height="46"><%=rs.getString("备注")%></td>
<td><a href="edit.jsp?ID=<%=a%>">修改信息</a> <a href="del.jsp?ID=<%=a%>">删除信息</a></td>
</tr>
<%}%>
</tbody>
</table>
<p align="center"> </p></td>
</tr>
</table>
</form>
</td>
</tr>
</table>
</div>
</body>
</html>
它的前一页主干部分
<form action="search.jsp" method="post" enctype="multipart/form-data" name="form1" id="form1">
<table width="76%" height="114" border="1" align="center" cellspacing="0" bordercolor="#CCCCCC" bgcolor="#FFFFFF">
<!--DWLayoutTable-->
<tr>
<td width="629" height="112" valign="top"><span class="STYLE6">
</span><span class="STYLE6">
<label> </label>
</span>
<label><div align="left"><span class="STYLE6">
</span>
<div align="center">
<div align="left"></div>
<div align="left"><span class="STYLE6">查询类别</span><span class="STYLE6">
<select name="style">
<option value="竞赛项目">竞赛项目</option>
<option value="时间">时间</option>
<option value="获奖等级">获奖等级</option>
<option value="获奖人">获奖人</option>
<option value="指导教师">指导老师</option>
<option value="备注">备注</option>
</select>
</span><br />
<br/>
<br/>
</div>
</div>
</div>
</label>
<span class="STYLE6"></span><span class="STYLE6"> </span>
<label class="STYLE6">
<div align="left">关键字
<input type="text" name="keyword" />
<input type="submit" name="Submit" value="查询" />
<a href="show.jsp">全部查询</a></div>
</label>
<label></label></td>
</tr>
</table>
<div align="center"></div>
<label></label>
</form>
二:我在修改数据库内容时出现 java.sql.SQLException: [Microsoft][ODBC Microsoft Access Driver] 参数不足,期待是 4。
大家帮帮忙吧 我的分数也不多 辛苦大家了!谢谢啦!