php create ICS文件在描述中显示HTML标签

I'm working on a php class that wil extract data from a SQL table to a ICS file for microsoft outlook.

here is the code in dpaste, it will last for a year.

And here is the code that calls the class to create a appointment

It almost works except de description has all the HTML tags in it see this screenshot:

Has anyone a idea how to fix this?

You seem to have a CRLF and spaces right before the X-ALT-DESC parameter so the client is handling it as part of the DESCRIPTION text, not as a parameter. You should remove all unnecessary CRLF and spaces in your code.

Then, you are aware that this X-ALT-DESC parameter is not standard at all. Other clients will probably show the html tags as well.