C# How to read display templates location in Sharepoint 2013

Question

Sharpeoint 2013 has a default filter template located at:

_catalogs/masterpage/Display%20Templates/Filters/Filter_Default.js

How can I read the absolute path of the _catalogs masterpage in C# ?

Example of absolute path : http://mymachine/_catalogs/masterpage/Display%20Templates/Filters/Filter_Default.js

so, if I'll load this file in a html script element, I will not get a 404 Not found error in the browser:

<script type="text/javascript" src="http://mymachine/_catalogs/masterpage/Display%20Templates/Filters/Filter_Default.js">
</script>

Answer 1

Why would you not use the fact that _catalogs is a virtual directory in SharePoint and reference it like this:

<scrit type="text/javascript" src="/_catalogs/15/masterpage/Display%20Templates/Filters/Filter_Default.js">
</script>

(notice the slash at first, and the 15 telling Sharepoint to look at the 15 hive instead of the 14 hive from 2010)

I also notice you have a typo in your "type" attribute (javscript instead of javascript)