SpringMVC中如何解决POST请求中文乱码问题

写在前面:这个只是问题只需要添加一个简单的配置就可以了,并且对应的代码在程序中是死的,我们只需要按照对应的格式进行编码就可以了。

本文主要解决的是POST和GET两种请求方式,希望对你有帮助!!!

1、POST乱码

1.1、在web.xml中配置

SpringMVC中,其为我们提供了过滤器CharacterEncodingFilter类 在该类中,有一个核心的方法:

public class CharacterEncodingFilter extends OncePerRequestFilter {

    ...
        
    @Nullable
    private String encoding;

    private boolean forceRequestEncoding = false;
    private boolean forceResponseEncoding = false;


    @Override
    protected void doFilterInternal(
        HttpServletRequest request, HttpServletResponse response, FilterChain filterChain)
        throws ServletException, IOException {

        String encoding = getEncoding();
        if (encoding != null) {
            if (isForceRequestEncoding() || request.getCharacterEncoding() == null) {
                request.setCharacterEncoding(encoding);
            }
            if (isForceResponseEncoding()) {
                response.setCharacterEncoding(encoding);
            }
        }
        filterChain.doFilter(request, response);
    }
}

我们只需要对该类中的核心的方法进行对应的配置,就可以完成对应的POST请求中文乱码

1.2、具体的处理方式

配置方式,在web.xml中添加下面的配置代码:

<filter>
    <filter-name>encoding</filter-name>
    <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
    <init-param>
        <param-name>encoding</param-name>
        <param-value>utf-8</param-value>
        <!-- 后面这两个可以不用添加 -->
        <param-name>forceEncoding</param-name>
        <param-value>true</param-value>
    </init-param>
</filter>
<filter-mapping>
    <filter-name>encoding</filter-name>
    <url-pattern>/*</url-pattern>
</filter-mapping>

2、GET乱码

2.1、在tomcat服务器中添加编码

apache-tomcat-8.5.37 --> conf --> server.xml

在第一个Connector标签中,添加对应的UTF编码

 <Connector URIEncoding="UTF-8"  port="8080" protocol="HTTP/1.1"
               connectionTimeout="20000"
               redirectPort="8443" />

3、使用一个万能的配置类(解决POST和GET)

编写对应的过滤器类,然后在web.xml中配置这个过滤器即可!

/**
 * 解决get和post请求 全部乱码的过滤器
 */
public class GenericEncodingFilter implements Filter {

    @Override
    public void destroy() {
    }

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
        //处理response的字符编码
        HttpServletResponse myResponse=(HttpServletResponse) response;
        myResponse.setContentType("text/html;charset=UTF-8");

        // 转型为与协议相关对象
        HttpServletRequest httpServletRequest = (HttpServletRequest) request;
        // 对request包装增强
        HttpServletRequest myrequest = new MyRequest(httpServletRequest);
        chain.doFilter(myrequest, response);
    }

    @Override
    public void init(FilterConfig filterConfig) throws ServletException {
    }

}

//自定义request对象,HttpServletRequest的包装类
class MyRequest extends HttpServletRequestWrapper {

    private HttpServletRequest request;
    //是否编码的标记
    private boolean hasEncode;
    //定义一个可以传入HttpServletRequest对象的构造函数,以便对其进行装饰
    public MyRequest(HttpServletRequest request) {
        super(request);// super必须写
        this.request = request;
    }

    // 对需要增强方法 进行覆盖
    @Override
    public Map getParameterMap() {
        // 先获得请求方式
        String method = request.getMethod();
        if (method.equalsIgnoreCase("post")) {
            // post请求
            try {
                // 处理post乱码
                request.setCharacterEncoding("utf-8");
                return request.getParameterMap();
            } catch (UnsupportedEncodingException e) {
                e.printStackTrace();
            }
        } else if (method.equalsIgnoreCase("get")) {
            // get请求
            Map<String, String[]> parameterMap = request.getParameterMap();
            if (!hasEncode) { // 确保get手动编码逻辑只运行一次
                for (String parameterName : parameterMap.keySet()) {
                    String[] values = parameterMap.get(parameterName);
                    if (values != null) {
                        for (int i = 0; i < values.length; i++) {
                            try {
                                // 处理get乱码
                                values[i] = new String(values[i]
                                        .getBytes("ISO-8859-1"), "utf-8");
                            } catch (UnsupportedEncodingException e) {
                                e.printStackTrace();
                            }
                        }
                    }
                }
                hasEncode = true;
            }
            return parameterMap;
        }
        return super.getParameterMap();
    }

    //取一个值
    @Override
    public String getParameter(String name) {
        Map<String, String[]> parameterMap = getParameterMap();
        String[] values = parameterMap.get(name);
        if (values == null) {
            return null;
        }
        return values[0]; // 取回参数的第一个值
    }

    //取所有值
    @Override
    public String[] getParameterValues(String name) {
        Map<String, String[]> parameterMap = getParameterMap();
        String[] values = parameterMap.get(name);
        return values;
    }
}