Question

What is the difference between these two declarations?

string str;
String str;

Answer 1

In normal usage, string and String are identical; string is simply an alias for global::System.String. There are some edge-cases, though:

• you need a using System; to use String – you don’t for string
• if you define a local class String {}, then String refers to that (this would be a silly thing to do, of course). You can’t define a class called string (although @string is fine)