CODEWITHSUNDEEP
htmlinternet-explorerwhitespace
zachleat
zachleat

Reputation: 3327

Inconsistent Whitespace Text Nodes in Internet Explorer

The following source code alerts the following results:

Internet Explorer 7: 29
Firefox 3.0.3: 37 (correct)
Safari 3.0.4 (523.12.9): 38
Google Chrome 0.3.154.9: 38

Please ignore the following facts:

Of the tags in the test page, the following tags have no whitespace text nodes inserted in the DOM after them: form, input[@radio], div, span, table, ul, a.

My question is: What is it about these nodes that makes them the exception in Internet Explorer? Why is whitespace not inserted after these nodes, and is inserted in the others?

This behavior is the same if you switch the tag order, switch the doctype to XHTML (while still maintaining standards mode).

Here's a link that gives a little background information, but no ideal solution. There might not be a solution to this problem, I'm just curious about the behavior.

Thanks Internet, Zach

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html>
    <head>
        <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
        <script type="text/javascript">
        function countNodes()
        {
            alert(document.getElementsByTagName('body')[0].childNodes.length);
        }
        </script>
    </head>
    <body onload="countNodes()">
        <form></form>
        <input type="submit"/>
        <input type="reset"/>
        <input type="button"/>
        <input type="text"/>
        <input type="password"/>
        <input type="file"/>
        <input type="hidden"/>
        <input type="checkbox"/>
        <input type="radio"/>
        <button></button>
        <select></select>
        <textarea></textarea>
        <div></div>
        <span></span>
        <table></table>
        <ul></ul>
        <a></a>
    </body>
</html>

Upvotes: 7

Views: 5870

Answers (5)

kaimagpie
kaimagpie

Reputation: 541

Zachleat, I think I've found a solution to the problem. (I've taken liberty of moving the form elements into the form tag.)

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<!--REF http://stackoverflow.com/questions/281443/inconsistent-whitespace-text-nodes-in-internet-explorer -->
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<script type="text/javascript">
    function countNodes()
    { alert(document.getElementsByTagName('form')[0].childNodes.length);
    };
</script>
</head>
<body onload="countNodes()">
  <form
    ><input type="submit"/
    ><input type="reset"/
    ><input type="button"/
    ><input type="text"/
    ><input type="password"/
    ><input type="file"/
    ><input type="hidden"/
    ><input type="checkbox"/
    ><input type="radio"/
    ><button></button
    ><select></select
    ><textarea></textarea
    ><div></div
    ><span></span
    ><table></table
    ><ul></ul
    ><a></a
  ></form>
</body>
</html>

As you can see, I've split & strapped the closing gt (greater-than) brackets so they hug to the next tag, thus ensuring there are no ambiguous whitespaces.

It was a nice surprise that it worked for all (4 desktop) browsers tried so far, all reporting the same number of DOM nodes.

Upvotes: 0

Kornel
Kornel

Reputation: 100110

IE tries to be helpful and hides text nodes that contain only whitespace.

In the following:

<p>
<input>
</p>

W3C DOM spec says that <p> has 3 child nodes ("\n", <input> and "\n"), IE will pretend there's only one.

The solution is to skip text nodes in all browsers:

var node = element.firstChild;
while(node && node.nodeType == 3) node = node.nextSibling;

Popular JS frameworks have functions for such things.

Upvotes: 10

Ishmael
Ishmael

Reputation: 32540

Why not just try walking the DOM and see what each browser thinks that the document contains?

IE does a lot of "optimization" of the DOM. To get an impression of what this might look like, "Select all", "Copy" in IE, and then "Paste Alternate" in Visual Studio, You get the following:

<INPUT value="Submit Query" type=submit> 
<INPUT value=Reset type=reset> 
<INPUT type=button> 
<INPUT type=text> 
<INPUT value="" type=password> 
<INPUT type=file> 
<INPUT type=hidden>
<INPUT type=checkbox>
<INPUT type=radio>
<BUTTON type=submit></BUTTON> 
<SELECT></SELECT>
<TEXTAREA></TEXTAREA>

So it nukes some of the empty tags and adds some default attributes.

Upvotes: 0

scunliffe
scunliffe

Reputation: 63588

I'm guessing that the table tag is different between browsers.

e.g. which nodes does the default table auto-magically contain?

<table>
  <thead>
  </thead>
  <tbody>
  </tbody>
  <tfoot>
  </tfoot>
</table>

Upvotes: 0

okoman
okoman

Reputation: 5657

Well... I'd say the reason it that it is IE. I don't think the programers had a specific intention to do it that way.

Upvotes: 0

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