I am trying to covert some VB.NET code to C# and found this interesting thing. Adding two chars returns different results in VB.NET and C#.
VB.NET -
In C# char is a 16-bit numeric type, so + means addition, not concatenation. Therefore, when you add a and b you get a+b. Moreover, the result of this addition is an int (see a quick demo).
If by "adding two characters" you mean "concatenation", converting them to a strings before applying operator + would be one option. Another option would be using string.Format, like this:
string res = string.Format("{0}{1}", charA, charB);