C# 7 Additions – Literals

A small, but nice chance in C# 7 is increased flexibility in literals. Previously, large numeric constants had no separator, and it was difficult to easily read a large number. For example, if you needed a constant for the number of stars in the observable universe (1,000,000,000,000,000,000,000), you’d have to do the following:

ulong numberOfStarsInTheUniverse = 10000000000000000000;

If you hadn’t caught the error, the constant is too short, and it’s difficult to tell looking at the numbers without a separator. In C# 7, it’s now possible to use the underscore (_) in between the numbers. So the previous example now becomes much easier to read, and it is easily recognizable the number is off.

ulong numberOfStarsInTheUniverse = 10_000_000_000_000_000_000; 
  //This is too short!

The new version adds binary constants too. Instead of writing a constant in hex, or decimal, a constant can now be written like so:

int defaultAdminFlag = 0b1000_0000_0000_0000_0000;