function checkNumber(value,van,tot){
	value = parseInt(value);
	if (isNaN(value) || value <= parseInt(van) || value > parseInt(tot)) return false; 
	return true;	
}
function checkString(value,length){
	if (value == '' ||value.length < length) return false;
	return true
}
function walkDOM(obj,spaties){
	tree='';
	for(var i=0;obj.childNodes[i];i++){
		if(obj.childNodes[i].nodeType==1){
			tree += spaties + '<' + obj.childNodes[i].nodeName.toLowerCase() + '>\n';
			tree += walkDOM(obj.childNodes[i],spaties+'  ');
		}
	}
	return tree;
}