xmlread then xmlwrite creates extra white space
Kevin Dufendach
file with extra carriage returns/line breaks/white space. Does anyone
know how to suppress this? It seems the answer may have something to
do with the xml:space attribute (per http://www.w3.org/TR/xml/#sec-white-space),
but I don't see this in my docNode object.
Example to reproduce:
docNode = xmlread('FileName.xml')
xmlwrite('FileName.xml', docNode)
Kevin Dufendach
-----------------------------------
% Set tempFileName
tempFileName = [tempname, '.xml'];
% Create XML document
docNode = com.mathworks.xml.XMLUtils.createDocument('root_element');
docRootNode = docNode.getDocumentElement;
myNode = docNode.createElement('myNode');
docRootNode.appendChild(myNode);
xmlwrite(tempFileName, docNode); edit(tempFileName);
%re-load tempFileName, then re-save it.
docNode = xmlread(tempFileName);
xmlwrite(tempFileName, docNode); edit(tempFileName);
-----------------------------------
First, the xml file produced is:
-----------------------------------
<?xml version="1.0" encoding="utf-8"?>
<root_element>
<myNode/>
</root_element>
-----------------------------------
And then, when it is read back in and then written, the xml produced
is:
-----------------------------------
<?xml version="1.0" encoding="utf-8"?>
<root_element>
<myNode/>
</root_element>
-----------------------------------
Thanks for the help,
Kevin
Some One
Hello Kevin,
I have also encountered this issue, and wasn't able to find a fix, or a reason why this happens.
However, I did manage to gather from several other posts a workaround that does the trick for me, it includes writing the document object to a string and then to file, with an intermediate step of fixing an encoding issue,
I summarized the steps in a function you can use which replaces the standard matlab xmlwrite function.
Hope this helps (if still relevant...:))
function ST = myXMLwrite(fileName, docNode)
docNodeRoot=docNode.getDocumentElement;
str=strrep(char(docNode.saveXML(docNodeRoot)), 'encoding="UTF-16"', 'encoding="UTF-8"');
fid=fopen(fileName, 'w');
fwrite(fid, str);
ST = fclose(fid);
Save the above function to myXMLwrite.m
then use as follows:
docNode=xmlread('somefile.xml);
%%%%%%%%%
% Do XML stuff %
%%%%%%%%%
myXMLwrite('somefile.xml', docNode);
Alex
Searched and Searched to no avail. This is what I currently use:
fileNode = xmlread(xmlFileName);
rootNode = cleanXML(fileNode.getDocumentElement);
function node = cleanXML(node)
% removes the whitespace nodes from matlab xmlread
for x = 1:node.getLength
child=node.item(x-1);
if(isa(child,'org.apache.xerces.dom.DeferredTextImpl'))
node.removeChild(child);
% element removed, length is no longer valid -- recurse
cleanXML(node);
break;
else
cleanXML(child);
end
end
Alex
rootnode = cleanXML(docNode.getDocumentElement)
xmlwrite('FileName.xml', docNode)
Witold
Added a new function that operates on the output string:
function XMLstring = xmlwrite_spec(varargin)
% treat input
if nargin==1
writeFlag = false;
FileName = '';
DOMnode = varargin{1};
elseif nargin==2
writeFlag = true;
FileName = varargin{1};
DOMnode = varargin{2};
else
error('Wrong number of arguments')
end
% treat output of xmlwrite
XMLstring = xmlwrite(DOMnode);
while 1
length_Old = length(XMLstring);
XMLstring = strrep(XMLstring,[char(32) char(10)],char(10));
if length_Old==length(XMLstring)
break
end
end
XMLstring = strrep(XMLstring,[char(10) char(10)],char(10));
% if demanded, write result to file
if writeFlag
FID = fopen(FileName,'w');
fwrite(FID,XMLstring);
fclose(FID);
end
Adam
Your code almost works as advertised, however I found that
if(isa(child,'org.apache.xerces.dom.DeferredTextImpl'))
node.removeChild(child);
will also remove any elements with actual text nodes.
eg <test>this is a test </test>
will be modified to be
<test/>
after running through cleanXML
I can't think of any other way to identify the pesky whitespace.
They don't seem to be consistent length or have other uniquely identifiable properties.
Any ideas?
Adam
"Alex " <kimm...@uregina.ca> wrote in message <im0ns9$dlk$1...@fred.mathworks.com>...
David
docNode = xmlread('FileName.xml');
docStr = xmlwrite(docNode);
docStr = regexprep(docStr,'\x0A\x0A','\n');
openDoc = fopen(''FileName.xml','w');
fprintf(openDoc,'%s\n',docStr);
fclose(openDoc);
Kevin Moerman
XML_string = xmlwrite(XDOC); %XML as string
XML_string = regexprep(S,'\n\t*\n','\n'); %removes tabs and extra lines
%Write to file
fid = fopen(save_name,'w');
fprintf(fid,'%s\n',XML_string);
fclose(fid);
Kevin
Kevin Moerman
Kevin Moerman
function write_XML_no_extra_lines(save_name,XDOC)
XML_string = xmlwrite(XDOC); %XML as string