Clone an XmlDocument and XmlResolver

EDN Admin · Apr 23, 2007

Hi,

I am using System.Xml to load and manipulate XHTML document. I have noticed that if I have a DOCTYPE directive in my xhtml file, my performance are very bad. I have done researches and I found that problem come from XmlResolver use to resolve entity reference. So I have made my own XmlResolver, which manage a local file cache.
For exemple

<div class=codeseg>
<div class=codecontent>
<div class=codesniptitle>Code Snippet XmlDocument doc = ();
doc.XmlResolver = ();
doc.Load(.OpenRead());
 

works fine and faster than

<div class=codeseg>
<div class=codecontent>
<div class=codesniptitle> doc = new XmlDocument(); 
doc.Load(File.OpenRead("MasterTemplate.htm"));


But my problem is I want to use the Clone method on my document. But Clone construct a new XmlDocument, with the default resolver, it takes long long time and I didnt find a way to use my own resolver.
For exemple 

<div class=codeseg>
<div class=codecontent>
<div class=codesniptitle>
XmlDocument doc = new XmlDocument();
doc.XmlResolver = new XmlCachedFileResolver();
doc.Load(File.OpenRead("MasterTemplate.htm")); 
XmlDocument res = (XmlDocument) doc.Clone(); 

is slower than
 

<div class=codeseg>
<div class=codecontent>
<div class=codesniptitle>
XmlDocument doc = new XmlDocument();
doc.XmlResolver = new XmlCachedFileResolver();
doc.Load(File.OpenRead("MasterTemplate.htm")); 
XmlDocument res = new XmlDocument();
res.XmlResolver = new XmlCachedFileResolver();
res.InnerXml = doc.InnerXml; 


My test result
Without DOCTYPE directive Load : 0.6 ms Clone : 0.06 ms
With DOCTYPE Load : 2075 ms Clone : 1884 ms
With DOCTYPE/custom resolver Load : 87 ms Clone : 1970 ms
With DOCTYPE/last solution Load : 83 ms InnerXml : 31 ms

There is a way to set a resolver for Clone method (or other solution to improve performance) ?

Thanks

 



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Clone an XmlDocument and XmlResolver

EDN Admin

Well-known member