title: Best way to get all bits of an enum flag?
body: <p>I have an enum with a Flags attribute.</p>
  
  <p>My question is, I'd like to get an integer bitmask of all of the options without manually combining all the bits myself. 
  I want to do this to compare to some other int field, and I want to protect in case a future developer ads more bit options to the enum.</p>
  
  <p>Another thing is the bits in my enum flags will be all manually assigned, so I cannot simply get the next value and subtract 1.</p>