------解决方法--------------------------------------------------------
数据库Mysql
+--------------+-------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+--------------+-------------+------+-----+---------+-------+
| id | int(11) | NO | PRI | | |
| UserName | varchar(10) | YES | | NULL | |
| UserPassword | varchar(10) | YES | | NULL | |
+--------------+-------------+------+-----+---------+-------+
java代码：
User.java(部分):public class User implements Serializable {
private int id;
private String username;
private String password;
UserAccess.java(部分): public void delete(String id) {
String sql = "delete form userinfo where id= "+ id;
Basedao dao = new Basedao();
dao.doInsert(sql);
}
UserMgr.java(部分)：public void delete(String id)
{
UserAccess ua = new UserAccess();
ua.delete(id);
}
UserServlet.java(部分)：public class UserServlet extends HttpServlet {
public void doGet(HttpServletRequest req, HttpServletResponse res)
throws ServletException, IOException {
req.setCharacterEncoding("gbk");
String type = req.getParameter("type");
res.setCharacterEncoding("gbk");
if (type.equals("login")) {
this.login(req, res);
} else if (type.equals("update")) {
this.update(req, res);
} else if (type.equals("add")) {
this.add(req, res);
} else if (type.equals("delete")) {
this.delete(req, res);
} else if (type.equals("list")) {
this.list(req, res);
} else if (type.equals("view")) {
this.list(req, res);
}
}
public void doPost(HttpServletRequest req, HttpServletResponse res)
throws ServletException, IOException {
this.doGet(req, res);
}
public void delete(HttpServletRequest req, HttpServletResponse res)
throws ServletException, IOException {
UserMgr mgr = new UserMgr();
String id = req.getParameter("id");
mgr.delete(id);
this.list(req, res);
}
}
jsp页面：
userlist.jsp
<%@page contentType="text/html;charset=gbk"%>
<%@page errorPage="error.jsp"%>
<%@page import="java.util.*,com.zhangxu.system.model.*"%> <style type="text/css">
<!--
body,td,th {
font-family: Courier New, Courier, monospace;
font-size: 14px;
}
body {
background-image: url(img/userlistbg.JPG);
}
-->
</style>
<CENTER> <H1>用户列表 </H1> </CENTER>
<HR size=5 color="#000000">
<CENTER> <a href="UserAdd.jsp">新增用户 </a> </CENTER>
<TABLE border=1 align=center>
<TR align=center>
<TD width="161">用户编号 </TD>
<TD width="175">用户名称 </TD>
<TD width="52">用户密码 </TD>
<TD colspan=3>操作 </TD>
</TR>
<TR>
<%
List list = (List)request.getAttribute("list");
for(int i=0;i <list.size();i++)
{
User user= (User)list.get(i);
%>
<TD> <%=user.getId()%> </TD>
<TD> <%=user.getUsername()%> </TD>
<TD>***** </TD>
<TD width="134"> <a href="UserServlet?type=view&id= <%=user.getId()%>"> <font size="+1" color="#FF0000">查看 </font> </a> </TD>
<TD width="166"> <a href="UserServlet?type=delete&id= <%=user.getId()%>"> <font size="+1" color="#0000FF">删除 </font> </a> </TD>
<TD width="73"> <a href="UserServlet?type=update&id= <%=user.getId()%>"> <font size="+1" color="#0000FF">修改 </font> </a> </TD>
</TR>
<%}%>
</TABLE>
当点删除的时候 ID传过去 但是数据库老报错 ：com.mysql.jdbc.exceptions.MySQLSyntaxErrorException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'where id= 3' at line 1
