How to identify zero-width character?

Question

Visual Studio 2015 found an unexpected character in my code (error CS1056)

How can I identify what the character is? It's a zero-width character so I can't see it. I'd like to know exactly what it is so I can work out where it comes from and how to fix it with a find-and-replace (I have many similar errors).

Here's an example. There's a zero-width character between x and y in the quote below:

x​y

It would be helpful just to tell me the name of the character in my example, but I'd also like to know generally how to identify characters myself.

Answer 1

I have a little bit of Javascript embedded within my explanation of Unicode which allows you to see the Unicode characters you copy/paste into a textbox. Your example looks like this:

Here you can see that the character is U+200B. Just searching for that will normally lead you to http://www.fileformat.info, in this case this page which can give you details of the character.

If you have the characters yourself within an application, Char.GetUnicodeCategory is your friend. (Oddly enough, there's no Char.GetUnicodeCategory(int) for non-BMP characters as far as I can see...)