基于web的应用开发都会涉及到编码问题，特别是中文编码，一直是开发人员常见问题之一，也最为初学者所困扰。我们知道计算机最初是按英语单字节字符设计的，现在很多软件及系统仍然默认使用ISO8859-1编码来表示。因此，有的时候处理中文字符就会出现乱码的现象。出现乱码不只是简单的由某个软件所造成的，很可能与系统或相关软件有关联影响。
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
例如在java的web应用中采用过滤器的方式进行编码处理，将所有来自浏览器的请求（request）转换为UTF-8，因为浏览器发过来的请求包根据浏览器所在的操作系统编码，可能是各种形式编码。网上这方面的源代码很多，下面就是编码过滤器的源代码。需要配置web.xml 激活该Filter。
SetCharacterEncodingFilter源文件
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package org.kyle.web.sample; 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.UnavailableException; public class SetCharacterEncodingFilter implements Filter { /** * The default character encoding to set for requests that pass through * this filter. */ protected String encoding = null; /** * The filter configuration object we are associated with. If this value * is null, this filter instance is not currently configured. */ protected FilterConfig filterConfig = null; /** * Should a character encoding specified by the client be ignored? */ protected boolean ignore = true; /** * Take this filter out of service. */ public void destroy() { this.encoding = null; this.filterConfig = null; } /** * Select and set (if specified) the character encoding to be used to * interpret request parameters for this request. * * @param request The servlet request we are processing * @param result The servlet response we are creating * @param chain The filter chain we are processing * * @exception IOException if an input/output error occurs * @exception ServletException if a servlet error occurs */ public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException { // Conditionally select and set the character encoding to be used if (ignore || (request.getCharacterEncoding() == null)) { String encoding = selectEncoding(request); if (encoding != null) request.setCharacterEncoding(encoding); } // Pass control on to the next filter chain.doFilter(request, response); } /** * Place this filter into service. * * @param filterConfig The filter configuration object * *encoding * UTF-8 * */ public void init(FilterConfig filterConfig) throws ServletException { this.filterConfig = filterConfig; this.encoding = filterConfig.getInitParameter("encoding"); String value = filterConfig.getInitParameter("ignore"); if (value == null) this.ignore = true; else if (value.equalsIgnoreCase("true")) this.ignore = true; else if (value.equalsIgnoreCase("yes")) this.ignore = true; else this.ignore = false; } /** * Select an appropriate character encoding to be used, based on the * characteristics of the current request and/or filter initialization * parameters. If no character encoding should be set, return * null. * * The default implementation unconditionally returns the value configured * by the encoding initialization parameter for this * filter. * * @param request The servlet request we are processing */ protected String selectEncoding(ServletRequest request) { return (this.encoding); } } /** * The default implementation unconditionally returns the value configured * by the encoding initialization parameter for this * filter. * * @param request The servlet request we are processing */ protected String selectEncoding(ServletRequest request) { return (this.encoding); } } |
