怎么样取得页面内层的数量？

Question

比如说，有div1,div2,div3……
我想知道，一共有多少层，怎么写？

Answer 1

var divarray=document.all.tags("div")
var k=divarray.length

Answer 2

<DIV style="z-index: 12; position: absolute">abc</div>
<DIV style="z-index: 12; position: absolute">abc</div>
<DIV style="z-index: 12; position: absolute">abc</div><br><br><br><br><input type=button value=ok onclick="cc()">
<script language=javascript>
function cc(){
var aa = document.getElementsByTagName("div");
var j = 0;
for (var i=0; i<aa.length; i++)
{
    if(aa[i].style.position!="")j++;
}
alert("本页面里共有 "+j+" 层！");}
</script><DIV style="z-index: 12; position: absolute">abc</div>
<DIV style="z-index: 12; position: absolute">abc</div>
<DIV style="z-index: 12; position: absolute">abc</div><br><br><br><br><input type=button value=ok onclick="cc()">
<script language=javascript>
function cc(){
var aa = document.getElementsByTagName("div");
var j = 0;
for (var i=0; i<aa.length; i++)
{
    if(aa[i].style.position!="")j++;
}
alert("本页面里共有 "+j+" 层！");}
</script><DIV style="z-index: 12; position: absolute">abc</div>
<DIV style="z-index: 12; position: absolute">abc</div>
<DIV style="z-index: 12; position: absolute">abc</div><br><br><br><br><input type=button value=ok onclick="cc()">
<script language=javascript>
function cc(){
var aa = document.getElementsByTagName("div");
var j = 0;
for (var i=0; i<aa.length; i++)
{
    if(aa[i].style.position!="")j++;
}
alert("本页面里共有 "+j+" 层！");}
</script><DIV style="z-index: 12; position: absolute">abc</div>
<DIV style="z-index: 12; position: absolute">abc</div>
<DIV style="z-index: 12; position: absolute">abc</div><br><br><br><br><input type=button value=ok onclick="cc()">
<script language=javascript>
function cc(){
var aa = document.getElementsByTagName("div");
var j = 0;
for (var i=0; i<aa.length; i++)
{
    if(aa[i].style.position!="")j++;
}
alert("本页面里共有 "+j+" 层！");}
</script><DIV style="z-index: 12; position: absolute">abc</div>
<DIV style="z-index: 12; position: absolute">abc</div>
<DIV style="z-index: 12; position: absolute">abc</div><br><br><br><br><input type=button value=ok onclick="cc()">
<script language=javascript>
function cc(){
var aa = document.getElementsByTagName("div");
var j = 0;
for (var i=0; i<aa.length; i++)
{
    if(aa[i].style.position!="")j++;
}
alert("本页面里共有 "+j+" 层！");}
</script>

Answer 3

SORRY！我一下复制就复了这么多，不好意思！
<DIV style="z-index: 12; position: absolute">abc</div>
<DIV style="z-index: 12; position: absolute">abc</div>
<DIV style="z-index: 12; position: absolute">abc</div><br><br><br><br><input type=button value=ok onclick="cc()">
<script language=javascript>
function cc(){
var aa = document.getElementsByTagName("div");
var j = 0;
for (var i=0; i<aa.length; i++)
{
    if(aa[i].style.position!="")j++;
}
alert("本页面里共有 "+j+" 层！");}
</script>

Answer 4

thank you 梅花雨，好同志！