无法 删除数据库记录 这是为什么啊
无法 删除数据库记录 这是为什么啊
connDB.JAVA文件
package com.netbean.web;
import java.sql.*;
import java.sql.DriverManager;
public class connDB{
Connection conn=null;
Statement stmt=null;
ResultSet rs=null;
public connDB(){
try{
Class.forName("com.mysql.jdbc.Driver");
}catch(java.lang.ClassNotFoundException e){
System.err.println(e.getMessage());
}
}
public ResultSet executeQuery(String sql){
try{
conn=DriverManager.getConnection("jdbc:mysql://localhost/test?user=root&password=sa");
stmt=conn.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,ResultSet.CONCUR_READ_ONLY);
rs=stmt.executeQuery(sql);
}catch(SQLException ex){
System.err.println(ex.getMessage());
}
return rs;
}
public int executeUpdate(String sql){
int result=0;
try{
conn=DriverManager.getConnection("jdbc:mysql://localhost/test?user=root&password=sa");
stmt=conn.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,ResultSet.CONCUR_READ_ONLY);
result=stmt.executeUpdate(sql);
}catch(SQLException ex){
result=0;
}
return result;
}
public void close(){
try {
if (rs != null) rs.close();
}
catch (Exception e) {
e.printStackTrace(System.err);
}
try {
if (stmt != null) stmt.close();
}
catch (Exception e) {
e.printStackTrace(System.err);
}
try {
if (conn != null) {
conn.close();
}
}
catch (Exception e) {
e.printStackTrace(System.err);
}
}
public String chStr_In(String str){
if(str==null){
str="";
}else{
try{
str=(new String(str.getBytes("iso-8859-1"),"GB2312")).trim();
str=str.replace('\'',(char)1);
}catch(Exception e){
e.printStackTrace(System.err);
}
}
return str;
}
public String chStr_Out(String str){
if(str==null){
str="";
}else{
try{
str=str.replace((char)1,'\'');
}catch(Exception e){
e.printStackTrace(System.err);
}
}
return str;
}
}
用来删除记录的 del。jsp文件
<%@ page contentType="text/html; charset=gb2312" language="java" import="java.sql.*" errorPage="" %>
<%@ page import="java.lang.*"%>
<jsp:useBean id="ConnDB" scope="page" class="com.netbean.web.ConnDB"/>
<jsp:useBean id="ChStr" scope="page" class="com.netbean.web.ChStr"/>
<jsp:include page="../huotaiguanli/safe.jsp"/>
<%
String sql="delete from news where Id=3";
int ret=0;
ret=ConnDB.executeUpdate(sql);
if (ret==1){
out.println("<script language='javascript'>alert('信息删除成功!');window.location.href='../huotaiguanli/news.jsp';</script>");
}else{
out.println("<script language='javascript'>alert('信息删除失败!');window.location.href='../huotaiguanli/news.jsp';</script>");
}
%>