Javascript learning note (2) when the mouse passes, the background color of the div block is changed

HTML code: viewsourceprint? 1 & lt; ul & gt; & nbsp; 2 & nbsp; & lt; li & gt; change the background color when the mouse passes through & lt; /li & gt; & nbsp; 3 & nbsp; & lt; li & gt; change the background color when the mouse passes through & lt; /li & gt;

Some HTML code:
View sourceprint? 1

2

• Changes the background color when the mouse passes

3

• Changes the background color when the mouse passes

4

• Changes the background color when the mouse passes

5

• Changes the background color when the mouse passes

6

Javascript code:
When the mouse passes, add the class = "current" to li. When the mouse leaves, remove the class to change the background color!
View sourceprint? 01 window. onload = function (){

02 var lis = document. getElementsByTagName ("li ");

03 for (var I = 0; I

04 lis [I]. onmouseover = function (){

05 this. setAttribute ("class", "current ");

06}

07 lis [I]. onmouseout = function (){

08 this. setAttribute ("class ","");

09}

10}

11}

Part of the css code:
View sourceprint? 1 ul li. current {

2 background-color: red;

3 cursor: pointer;

4}