大家好：
    我想请教的问题是：
     为了处理乱码问题 我写了个过滤器，设置字符编码为来处理htm提交的form表单，但是就是不起作用；我想请问是怎么回事情啊?
   过滤代码如下：
       package global;

import

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;

public class EncodingFilter implements Filter {
    protected FilterConfig filterConfig;

    public void init(FilterConfig config) throws ServletException {
        this.filterConfig = config;

    }

    public void doFilter(final ServletRequest req, final ServletResponse res,
            FilterChain chain) throws IOException, ServletException {
            req.setCharacterEncoding("gb2312");
       chain.doFilter(req, res);
    }
    public void destroy() {
        this.filterConfig = null;
    }

}