Web Project 3 乱码解决方案小结

1. 数据库乱码
使用EMS SQL Manager for MySQL可以容易地解决这个问题，在table的属性对话框中将Character Set设为GBK即可。

2. Ajax应用中Servlet返回内容乱码
设置响应报头的编码即可
response.setHeader("Content-Type", "text/html;charset=GB2312");

3. JSP页面显示乱码
在页面开头加上
<%@ page pageEncoding="GBK"%>

4. request.getParameter产生乱码
用post方法只要在获取参数前设置编码即可
request.setCharacterEncoding("GBK");
get方法还需要在获取参数后转换编码
name = new String(name.getBytes("ISO8859-1"), "GBK");

5. google到的另一个解决方法，不过貌似不成功 -,-

package  filter;

import  javax.servlet.Filter;
import  javax.servlet.FilterConfig;
import  javax.servlet.ServletException;
import  javax.servlet.ServletRequest;
import  javax.servlet.ServletResponse;
import  javax.servlet.FilterChain;
import  java.io.IOException;

public   class  EncodingFilter  implements  Filter  {
  protected FilterConfig filterConfig;

  protected String encodingName;

  protected boolean enable;

  public EncodingFilter() {
    this.encodingName = "UTF-8";
    this.enable = false;
  }

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

  private void loadConfigParams() {
    this.encodingName = this.filterConfig.getInitParameter("encoding");
    String strIgnoreFlag = this.filterConfig.getInitParameter("enable");
    if (strIgnoreFlag.equalsIgnoreCase("true")) {
      this.enable = true;
    } else {
      this.enable = false;
    }
  }

  public void doFilter(ServletRequest request, ServletResponse response,
      FilterChain chain) throws IOException, ServletException {
    if (this.enable) {
      request.setCharacterEncoding(this.encodingName);
    }
    chain.doFilter(request, response);
  }

  public void destroy() {
  }
}

web.xml

  < filter >
     < filter-name > EncodingFilter </ filter-name >
     < filter-class > filter.EncodingFilter </ filter-class >
     < init-param >
       < param-name > encoding </ param-name >
       < param-value > UTF-8 </ param-value >
     </ init-param >
     < init-param >
       < param-name > enable </ param-name >
       < param-value > true </ param-value >
     </ init-param >
   </ filter >
   < filter-mapping >
     < filter-name > EncodingFilter </ filter-name >
     < url-pattern > /user/* </ url-pattern >
   </ filter-mapping >
   < filter-mapping >
     < filter-name > EncodingFilter </ filter-name >
     < url-pattern > /manager/* </ url-pattern >
   </ filter-mapping >