Struts1 中提交中文表单到ActionForm后出现乱码问题的原因及处理方法

问题：

在你所有页面设置的编码都是utf-8的情况下仍然会出现中文乱码现象。

一、乱码出现原因

由于Struts框架直接把表单数据发送给了ActionForm，所以这里面没有对HttpRequestServlet进行SetCharacterEncoding,所以默认是按照ISO-8859-1。

二、解决办法

方法 ： 就是在表单提交到ActionForm之前对request进行编码,写一个过滤器，对所有请求进行过滤

方式一：直接在过滤器中指定编码格式

MyFilter.java

public class MyFilter extends HttpServlet implements Filter {
    private static final long serialVersionUID = 1L;
       

    public void doFilter(ServletRequest arg0, ServletResponse arg1, FilterChain arg2) throws java.io.IOException, javax.servlet.ServletException { 
         // TODO Auto-generated method stub
          arg0.setCharacterEncoding("utf-8"); //设置接收编码
        arg1.setContentType("text/html;charset=utf-8");
        arg2.doFilter(arg0, arg1);   //必须
    
    }

    
    public void init(FilterConfig arg0) throws javax.servlet.ServletException { 
         // TODO Auto-generated method stub
    }

}

在web.xml中添加

<filter>
    <filter-name>MyFilter</filter-name>
    <filter-class>com.xidian.filter.MyFilter</filter-class>
  </filter>
  <filter-mapping>
    <filter-name>MyFilter</filter-name>
    <url-pattern>/*</url-pattern>
  </filter-mapping>

方式二：在web.xml中指定编码格式

MyFilter.java

package com.xidian.filter;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;

public class MyFilter extends HttpServlet implements Filter {
    private static final long serialVersionUID = 1L;
     private String encoding; 

    public void doFilter(ServletRequest arg0, ServletResponse arg1, FilterChain arg2) throws java.io.IOException, javax.servlet.ServletException { 
         // TODO Auto-generated method stub
           arg0.setCharacterEncoding(encoding);
           arg2.doFilter(arg0, arg1);
    }

    public void init(FilterConfig arg0) throws javax.servlet.ServletException { 
         // TODO Auto-generated method stub
         encoding=arg0.getInitParameter("encoding");
    }

}

在web.xml添加

 <filter>
    <filter-name>MyFilter</filter-name>
    <filter-class>com.xidian.filter.MyFilter</filter-class>
    <init-param>
    <param-name>encoding</param-name>
    <param-value>utf-8</param-value>
    </init-param> 
  </filter>
  <filter-mapping>
    <filter-name>MyFilter</filter-name>
    <url-pattern>/*</url-pattern>
  </filter-mapping>

下面是struts2中中文乱码的问题：

关于struts2中表单提交时，中文乱码问题的解决

顺带再说下加上对输入数据内容的过滤的情况：

再添加一个过滤程序：

SafeFilter.java

package com.xidian.filter;

import java.io.IOException;
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 SafeFilter implements Filter {    
    private String keywords[];

    public void doFilter(ServletRequest request, ServletResponse response,
            FilterChain chain) throws IOException, ServletException {
        //这里我们接收到用户名
        String name=request.getParameter("name");
        request.setAttribute("err", "您不允许登录<font color='red'>"+name+"</font>");
        System.out.println("第二个过滤器："+name);
        if(name!=null){
            //判断
            for(String key:keywords){
                if(key.equals(name)){
                    request.getRequestDispatcher("WEB-INF/ifo.jsp").forward(request, response);
                    return;
                }
            }
            
        }
        chain.doFilter(request, response);
    }


    public void init(FilterConfig filterConfig) throws ServletException {
        keywords=filterConfig.getInitParameter("keywords").split(";");

    }

}

web.xml的配置

<!-- 部署过滤器的顺序就是执行的顺序 -->
   <filter>
    <filter-name>MyFilter</filter-name>
    <filter-class>com.xidian.filter.MyFilter</filter-class>
    <init-param>
    <param-name>encoding</param-name>
    <param-value>utf-8</param-value>
    </init-param> 
  </filter>
 
   <filter>
    <filter-name>SafeFilter</filter-name>
    <filter-class>com.xidian.filter.SafeFilter</filter-class> 
    <init-param>
    <param-name>keywords</param-name>
    <param-value>拉登;小明;凤姐</param-value>
    </init-param>
  </filter>