How to safely encode HTML code that can already be encoded in HTML format?

Question

I need HTML to encode some text that may or may not already be encoded in HTML (perhaps only partially). Is the following safe? Are there any characters / encodings that can cause unexpected behavior?

HttpUtility.HtmlEncode(HttpUtility.HtmlDecode(text)) 

thanks

Answer 1

Your logic " HttpUtility.HtmlEncode(HttpUtility.HtmlDecode(text)) " is safe. There is a standard HTML character encoding. Take a look.

Answer 2

No built-in features. But I would use:

  return HttpUtility.HtmlDecode(text)!=text ? text : HttpUtility.HtmlEncode(text);