Question

Here’s some C# code:

var sb = new StringBuilder(); var w = XmlWriter.Create(sb); w.WriteStartElement('hello'); w.WriteAttributeString('target', 'world ' \' !'); w.WriteEndElement(); w.Flush(); // then look at sb.ToString() 

I’m getting a string that looks like:

 <?xml version='1.0' encoding='utf-16'?><hello target='world ' &quot; !' />  

It’s only escaping the double-quote, not the single-quote. But the docs for XmlWriter.WriteAttributeString(String, String) say:

If the attribute value includes double or single quotes, they are replaced with " and ' respectively.

Is there some flag I need to set to make it do what the docs say it does?

Answer 1

If you use .Net Reflector to look at the code, you’ll find that the System.Xml.XmlTextEncoder.Write(string) method is being called. Here’s the code of interest:

if (!this.inAttribute || (this.quoteChar != ch))    this.textWriter.Write('\''); else    this.WriteEntityRefImpl('apos'); 

When writing an attribute value, a single quote is not escaped since it doesn’t need to be. It’s only when writing a text element that ‘'’ is used.