In C#, is there a way to add an XML node to a file on disk WITHOUT loading it first?

Question

I have a very basic XML structure/file on disk which is something like:

    kdkdkdk         


        

Answer 1

Not with any XML API or tool.

You could open the file as Text, find the Position of and start overwriting from there. And of course add the again.

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A quick and dirty approach, this is not very robust:

• make sure you prep the initial file, there should be nothing (no whitespace) after the closing tag
• make sure you use ASCII or UTF8 encoding

====

string closeTag = "";
int closeLength = Encoding.UTF8.GetBytes(closeTag).Length;

var fs = System.IO.File.Open(filename, System.IO.FileMode.Open);
fs.Position = fs.Length - closeLength;

var writer = new StreamWriter(fs);  // after the Position is set

writer.WriteLine(newTag);
writer.Write(closeTag);  // NOT WriteLine !!

writer.Close();
fs.Close();

And of course you know about using using() {} blocks.