Ler contéudo dos campos no arquivo XML

ex.:
var descricao = pegaValor(item.getElementsByTagName("descricao")[0]);

function pegaValor(no){
if(no.childNodes.length>0){
return no.firstChild.nodeValue;
}else{
try{
return no.nodeValue;
}catch(e){
return " ";
}
}
}

OU:


function getElementText( xml, tagName ){
return xml.getElementsByTagName(tagName).item(0).text;
}

function getNodeValue(obj,tag){
return obj.getElementsByTagName(tag)[0].firstChild.nodeValue;
}