July 3, 2001 - Reading an Attribute Node in IE6 and NS6 | WebReference

July 3, 2001 - Reading an Attribute Node in IE6 and NS6

Yehuda Shiran July 3, 2001
Reading an Attribute Node in IE6 and NS6
Tips: July 2001

Yehuda Shiran, Ph.D.
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Unlike Internet Explorer 5.5 that supports only setAttribute() and getAttribute(), Internet Explorer 6 (as well as Netscape 6) supports also setAttributeNode() and getAttributeNode(). The method getAttributeNode() adds an attribute object to an existing DOM node. Here is the syntax:

elementNode.getAttributeNode(attributeObject);
where:

elementNode is a tag node. It mush have been created with the createElement() method.
  • attributeObject is an object that must have been created with the createAttribute() method.

    Here is a sample code which first creates an object, nodePublishDate, that is equal to today's date. It then creates a tag element node ("P"), and finally converts this latter node to an attribute node:

    var nodeBook, nodePublishDate;
nodePublishDate = document.createAttribute("PublishDate");
nodePublishDate.value = String(Date());
nodeBook = document.createElement("P");
nodeBook.setAttributeNode(nodePublishDate);

    We put it in a conditional statement in the header of this tip:

    if (bVer() >= 6) {
  var nodeBook, nodePublishDate;
  nodePublishDate = document.createAttribute("PublishDate");
  nodePublishDate.value = String(Date());
  nodeBook = document.createElement("P");
  nodeBook.setAttributeNode(nodePublishDate);
}

    Click the following buttons to see that indeed nodeBook is an attribute node. The name of the attribute is PublishDate and its value is today's date:

    Here is how we define the buttons above:

    <FORM>
<INPUT TYPE="button" VALUE="getAttribute('PublishDate')" 
  onClick="javascript:if (bVer()>=6) {alert(nodeBook.getAttribute('PublishDate'))} 
  else {alert('You must use Netscape 6 (or higher) or Internet Explorer 6 (or higher)')}">
<INPUT TYPE="button" VALUE="getAttributeNode('PublishDate').value" 
  onClick="javascript:if (bVer()>=6) {alert(nodeBook.getAttributeNode('PublishDate').value)} 
  else {alert('You must use Netscape 6 (or higher) or Internet Explorer 6 (or higher)')}">
</FORM>

    The browser version is computed by the bVer() function:

    function bVer() {
  // return version number (e.g., 4.03)
  msieIndex = navigator.appVersion.indexOf("MSIE") + 5;
  return(parseFloat(navigator.appVersion.substr(msieIndex,3)));
}

    Notice the usage of the getAttributeNode() method above. Also, notice the similarity between getAttribute() and getAttributeNode().