通过js修改doctype类型

直接上代码啦:

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd"> 
<html> 
<head> 
  <title>Untitled</title> 
</head> 
<body> 
<script type="text/javascript"> 
function foo() { 
  alert("document.body.parentNode.previousSibling.tagName\n" + document.body.parentNode.previousSibling.tagName); 
  alert("document.body.parentNode.parentNode.firstChild.tagName\n" + document.body.parentNode.parentNode.firstChild.tagName); 
  alert("document.body.parentNode.parentNode.firstChild.nodeName\n" + document.body.parentNode.parentNode.firstChild.nodeName); 
  alert("document.body.parentNode.parentNode.firstChild.nodeValue\n" + document.body.parentNode.parentNode.firstChild.nodeValue); 
  alert("document.body.parentNode.parentNode.lastChild.tagName\n" + document.body.parentNode.parentNode.lastChild.tagName); 
  alert("document.body.parentNode.parentNode.lastChild.nodeName\n" + document.body.parentNode.parentNode.lastChild.nodeName); 
} 
function redoctypeme(which) { 
  alert("before\n" + document.body.parentNode.parentNode.firstChild.nodeValue); 
  if(which == 1) { 
    document.body.parentNode.parentNode.firstChild.nodeValue = "DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01//EN\" \"http://www.w3.org/TR/html4/strict.dtd\""; 
  } 
  else { 
    document.body.parentNode.parentNode.firstChild.nodeValue = "DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\""; 
  } 
  alert("after\n" + document.body.parentNode.parentNode.firstChild.nodeValue); 
  foobar = document.body.innerHTML; 
  alert("empty"); 
  document.body.innerHTML = ""; 
  alert("reset"); 
  document.body.innerHTML = foobar; 
} 
</script> 
<a href="javascript: foo()">stuff</a> 
<a href="javascript: redoctypeme('1')">doctype 1</a> 
<a href="javascript: redoctypeme('2')">doctype 2</a> 
<hr> 
<div style="background: #0c0; width: 200px; color: #fff;">200px</div> 
<div style="background: #c00; width: 200px; padding: 20px; border: 30px solid #00c;"> </div> 
<div style="background: #0c0; width: 300px; color: #fff;">300px</div> 
</body> 
</html> 

  

posted @ 2011-12-21 13:11 learn_javascript 阅读(...) 评论(...) 编辑 收藏