jsp写入中文到mysql乱码问题

记录一下写作业遇到的问题

纠结了很久，代码是用servlet来处理form

其中post传输用户信息时一直乱码，最后查了半天才找见解决方法

 

1. 在jsp页面的<%@ page 位置加上 contentType=”text/html; charset=utf-8″ %>，<meta 的位置也是如此：content=”text/html;charset=utf-8″ />
2. 建立一个mysql数据库,字符集采用utf-8,建表也是如此。
3. 在getConnection的URL中加上：?useUnicode=true&characterEncoding=UTF-8″，如：url = “jdbc:mysql://localhost:3306/(此处为数据库名称)?useUnicode=true&characterEncoding=UTF-8″，也就是在（数据库名称）的后面  //其中问号不能丢
4. 如果你不是在jsp页面里直接处理form，也是和我一样采用servlet来处理form的话，那么在还要增加一个过滤器，这主要是因为采用的是tomcat的web发布器，如果用resin的话，不会有这样的问题。
   
   package UserSystem.filter; /** * Created by Ruilin on 2017/12/19. */ 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; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletRequestWrapper; public class SetCharacterEncodingFilter implements Filter { class Request extends HttpServletRequestWrapper { public Request(HttpServletRequest request) { super(request); } public String toChi(String input) { try { byte[] bytes = input.getBytes("ISO8859-1"); return new String(bytes, "utf-8"); } catch (Exception ex) { } return null; } private HttpServletRequest getHttpServletRequest() { return (HttpServletRequest) super.getRequest(); } public String getParameter(String name) { return toChi(getHttpServletRequest().getParameter(name)); } public String[] getParameterValues(String name) { String values[] =getHttpServletRequest().getParameterValues(name); if (values != null) { for (int i = 0; i < values.length; i++) { values[i] = toChi(values[i]); } } return values; } } public void destroy() { } public void doFilter(ServletRequest request, ServletResponse response,FilterChain chain) throws IOException, ServletException { HttpServletRequest httpreq = (HttpServletRequest) request; if (httpreq.getMethod().equals("POST")) { request.setCharacterEncoding("utf-8"); } else { request = new Request(httpreq); } chain.doFilter(request, response); } public void init(FilterConfig filterConfig) throws ServletException { } }

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   package UserSystem.filter;   /** * Created by Ruilin on 2017/12/19. */ 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; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletRequestWrapper;   public class SetCharacterEncodingFilter implements Filter {     class Request extends HttpServletRequestWrapper     {         public Request(HttpServletRequest request) {             super(request);         }         public String toChi(String input) {             try {                 byte[] bytes = input.getBytes("ISO8859-1");                 return new String(bytes, "utf-8");             } catch (Exception ex) {             }             return null;         }         private HttpServletRequest getHttpServletRequest()         {             return (HttpServletRequest) super.getRequest();         }         public String getParameter(String name)         {             return                     toChi(getHttpServletRequest().getParameter(name));         }         public String[] getParameterValues(String name)         {             String values[] =getHttpServletRequest().getParameterValues(name);             if (values != null) {                 for (int i = 0; i < values.length; i++) {                     values[i] = toChi(values[i]);                 }             }             return values;         }     }     public void destroy() {     }     public void doFilter(ServletRequest request, ServletResponse             response,FilterChain chain) throws IOException, ServletException {         HttpServletRequest httpreq = (HttpServletRequest) request;         if (httpreq.getMethod().equals("POST")) {             request.setCharacterEncoding("utf-8");         } else {             request = new Request(httpreq);         }         chain.doFilter(request, response);     }     public void init(FilterConfig filterConfig) throws             ServletException {     } }

   
   然后在WEB-INF目录下的web.xml文件，配置下过虑器
   
   <filter> <filter-name>SetCharacterEncodingFilter</filter-name> <filter-class>UserSystem.filter.SetCharacterEncodingFilter</filter-class> </filter> <filter-mapping> <filter-name>SetCharacterEncodingFilter</filter-name> <url-pattern>/*</url-pattern> </filter-mapping>

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   <filter>         <filter-name>SetCharacterEncodingFilter</filter-name>         <filter-class>UserSystem.filter.SetCharacterEncodingFilter</filter-class>     </filter>     <filter-mapping>         <filter-name>SetCharacterEncodingFilter</filter-name>         <url-pattern>/*</url-pattern>     </filter-mapping>

   
    

 

参考：http://blog.sina.com.cn/s/blog_6c5ad3d10100ligv.html