js xml - IF it exists, then show it

[cowsdonthack]

I'm working with an XML file, and I want to display all of it's properties using a format. I'm using "FOR"http://w3schools.com/ajax/ajax_xmlhttprequest_response.aspLike in this example, it pulls up the Artist and AlbumIt's dependant that the <Artist> and the <Album> tag is going to be there, but what if something goes missing?Then none of it works at all.The XML file I'm given has something like<EVENTS> <A> <B></B><C></C> </A> <A> <C></C> </A> <A> <B></B> </A></EVENTS>Using javascript, I have a script thatFor Each AShow B and CHow would I get it to show C if it exists, and B if it exists, without returning blank?

[ApocalypeX]

...var txt="";    x=xmlDoc.getElementsByTagName("A");    for (i=0;i<x.length;i++)      {      b = x[i].getElementsByTagName("B");      c = x[i].getElementsByTagName("C");	  if( B ){		txt += x[i].getElementsByTagName("B").childNodes[0].nodeValue;	  }	  if( C ){		txt += x[i].getElementsByTagName("C").childNodes[0].nodeValue;	  }      }	  else{	  	  }...