我测试的浏览器是'Firefox/3.0.6', IE 6.0两个。IE6.0 支持所有的属性,Firefox/3.0.6只支持innerHTML,其余几个都提示 'undefined'
innerHTML 设置或获取位于对象起始和结束标签内的 HTML
outerHTML 设置或获取对象及其内容的 HTML 形式
innerText 设置或获取位于对象起始和结束标签内的文本
outerText 设置(包括标签)或获取(不包括标签)对象的文本

Code
1 <div id="first">Testing the outerHTML Content <span id="second"> and innerHTML Content</span></div>
2
3 <input type="button" name="1innerh" onclick="alert(document.getElementById('first').innerHTML);" value="innerHTML"/>
4 <input type="button" name="1outerh" onclick="alert(document.getElementById('first').outerHTML);" value="outerHTML"/>
5 <input type="button" name="1innert" onclick="alert(document.getElementById('first').innerText);" value="innerTEXT"/>
6 <input type="button" name="1inner" onclick="alert(document.getElementById('first').outerText);" value="outerText"/>
7 <br />
8 <input type="button" name="2innerh" onclick="alert(document.getElementById('second').innerHTML);" value="second innerHTML"/>
9 <input type="button" name="2outerh" onclick="alert(document.getElementById('second').outerHTML);" value="second outerHTML"/>
10 <input type="button" name="2innert" onclick="alert(document.getElementById('second').innerText);" value="second innerTEXT"/>
11 <input type="button" name="2inner" onclick="alert(document.getElementById('second').outerText);" value="second outerText"/>
InnerHTML 按钮输出: Testing the outerHTML Content <SPAN id="second"> and innerHTML Content</span>
outerHTML 按钮输出: <DIV id="first">Testing the outerHTML Content <SPAN id="second"> and innerHTML Content</SPAN></DIV>
innerText 按钮输出: Testing the outerHTML Content and innerHTML Content
outerText 按钮输出: Testing the outerHTML Content and innerHTML Content
second InnerHTML 按钮输出: and innerHTML Content
second outerHTML 按钮输出: <SPAN id="second"> and innerHTML Content</SPAN>
second innerText 按钮输出: and innerHTML Content
second outerText 按钮输出:
and innerHTML Content