调试易

首先查一下你数据库里的字符集是否设置好 show variables like "%char%";
mysql> show variables like "%char%";
+--------------------------+-------------------------------------------------------+
| Variable_name            | Value
                                                                                   |
+--------------------------+-------------------------------------------------------+
| character_set_client     | utf8
                                                                                   |
| character_set_connection | utf8
                                                                                   |
| character_set_database   | utf8
                                                                                   |
| character_set_results    | utf8
                                                                                   |
| character_set_server     | utf8
                                                                                   |
| character_set_system     | utf8
                                                                                   |
| character_sets_dir       | C:\Program Files\MySQL\MySQL Server5.0s\hare\charsets\ |
+--------------------------+-------------------------------------------------------+

你试试每次登录之后都用以下语句进行设置：
SET CHARACTER_SET_CLIENT = utf8;
SET CHARACTER_SET_CONNECTION = utf8;
SET CHARACTER_SET_DATABASE = utf8;
SET CHARACTER_SET_RESULTS = utf8;
SET CHARACTER_SET_SERVER = utf8;
SET COLLATION_CONNECTION = utf8_bin;
SET COLLATION_DATABASE = utf8_bin;
SET COLLATION_SERVER = utf8_bin;
其中utf8和utf8_bin可以替换成你所需要的字符集，应该注意的是：该字符集应与你在MySQL数据库配制向导中所选择的字符集一致。

这是我总结的一些解决方案，不知对LZ有帮助没
1： 安装MySQL数据库时候就指定字符集合为gbk或者gb2312,只要数据库中显示正常中文字符的话，页面肯定显示正常，哪来这么多的转换，烦死了！！
2： 指定服务器的 编码   GBK   或者GB23123： 修改安装目录下的  初始化配置文件   my.ini# The TCP/IP Port the MySQL Server will listen on
port=3306
#Path to installation directory. All paths are usually resolved relative to this.
basedir="E:/MySQL5/"#Path to the database root
datadir="E:/MySQL5/Data/"# The default character set that will be used when a new schema or table is
# created and no character set is defined
default-character-set=latin1             换成  gbk   或者  gb2312# The default storage engine that will be used when create new tables when
default-storage-engine=INNODB

1：把你从数据库中取出来的字符串（str）用下面这个语句转换一遍
String newstr=new String(str.getBytes("8859_1"),"gb2312"); 
2：把你的数据库的字符集改为gb2312。