原来访问地址http://localhost/index.php/home/demo/editcourse中有个表单，
表单<form action="{:U('Home/Index/index')}" method="post">，提交表单后跳转到了http://localhost/index.php/home/demo/editcourse/Home/Index/index.html
为何不是http://localhost/index.php/Home/Index/index.html