Determine If A Tag or Node Exists

coolpeep · November 26th, 2003, 07:22 AM

Howdy,

I am retreiving a XML response from a xmlhttp "Post" using the following

.....getElementsByTagName("responseTag").item(0).t ext

My question is: How do I determine if a specific tag exists without causing generating an error? If I attempt to specify a tag name like the above example and it is not present then I get an error. Some of the responses are different per request but most of the retured information is the same.

How can I work around this?

Thanks in Advance,
CoolPeep

olmec · June 14th, 2006, 07:16 PM

The way I got round this issue was to read the parent node xml and then check it using a string compare to see if the child node was there. If it was then load that node.

<html>
  <head>
    <script>.........</script>
  </head>
</html>

if head.xml contains "<script" then load head child node script.

Not an elegant solution but it works for the quick job I have to do.

bobduncan · July 20th, 2006, 06:16 PM

Could you please be more specific on how to do this? I am connecting with an xml file using javascript and need to determine weather or not a tag or node exists. If the tage exists, a variable is incremented. If not, it stays the same:

var one = response.getElementsByTagName("job").childnodes.on e;
n = 0;
if ( typeof (one) == null ) { n = 9 }
else { n++; }
alert (n);

Thanks,
Bob
http://www.thehappypixel.com