function update_xml( xml_path , new_record)
if ~exist(xml_path,'file')
%创建
docNode = com.mathworks.xml.XMLUtils.createDocument('recognition_record');
else
%读入
docNode = xmlread(xml_path);
end
docRootNode = docNode.getDocumentElement();
% a new record
recordNode = docNode.createElement('record');
docRootNode.appendChild(recordNode);
% name
nameNode = docNode.createElement('name');
nameNode.appendChild(docNode.createTextNode(sprintf(new_record.name)));
recordNode.appendChild(nameNode);
% time
timeNode = docNode.createElement('time');
timeNode.appendChild(docNode.createTextNode(sprintf(new_record.time)));
recordNode.appendChild(timeNode);
% score_thres
thresNode = docNode.createElement('score_threshold');
thresNode.appendChild(docNode.createTextNode(sprintf(num2str(new_record.score_thres))));
recordNode.appendChild(thresNode);
% 写入文件
xmlwrite(xml_path , docNode);
end