几种java乱码情况解决方法:
1、在Servlet中获得通过get方式传递到服务器的数据时出现乱码;
public class RegistServlet extends HttpServlet{ @Override protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { String name = req.getParameter("userName"); byte[] bytes = name.getBytes("ISO8859-1"); String newName = new String(bytes,"UTF-8"); } @Override protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { doGet(req, resp); } }
解析:在doGet方法中定义一个name变量获得封装在服务器的客户端数据userName,然后将name以“ISO8859-1”的方式赋值给字节数组bytes,最后将此bytes数组以UTF-8的方式赋值给一个新创建的String变量newName,此时newName就是能正常显示的数据,之所以这么麻烦,是因为没有直接的办法一行代码解决,可以就当此方法为固定用法。
2、在Servlet中获得通过post方式传递到服务器的数据时出现乱码;
public class RegistServlet extends HttpServlet{ @Override protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { //注意:post方式提交数据的乱码解决方式,放在getParameXXX方法之前 req.setCharacterEncoding("UTF-8"); //得到前台input框中name="username"和password="password"的value值 String username = req.getParameter("username"); String password = req.getParameter("password"); } @Override protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { doGet(req, resp); } }
解析:post传递方式下解决乱码问题很简单,就req.setCharacterEncoding(“UTF-8”); 这一行代码,但需注意,要将这句话放在获取数据之前。
3、Servlet通过服务器将数据响应到客户端时出现乱码;
public class RegistServlet extends HttpServlet{ @Override protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { //方式一: resp.setContentType("text/html;charset=utf-8"); //方式二: resp.setHeader("Content-type", "text/html"); resp.setCharacterEncoding("UTF-8"); } @Override protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { doGet(req, resp); } }
解析:注意,以上两种方法在应用时要写在输出方法之前,另外,两种方式效果一样,因为方式一较简洁,常用方式一。
4、HTML或JSP页面在客户端展示时出现的乱码情况。
<head> <meta charset="UTF-8"> <meta http-equiv="Content-Type" content="text/html;charset=utf-8"> <title>form表单</title> </head>