[求助]如何在JSP中产生alert对话框
<%@page contentType="text/html;charset=UTF-8" %><% request.setCharacterEncoding("UTF-8"); String name = (String)request.getParameter("username"); String password = (String)request.getParameter("password"); if(name==null||password==null){ out.print("<script>alert('用户名或密码不能为空!');</script>");%><jsp:forward page="login.jsp"/><% } if(name.equals("samuelson")&&password.equals("000000")){%><jsp:forward page="success.jsp"/><% }else{//我这句话执行不出,怎么回事呢 out.print("<script>alert('用户名或密码错误!');</script>");%><jsp:forward page="login.jsp"/><% }%>