C# Programming/Keywords/global

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The global keyword is useful in some contexts to resolve ambiguity between identifiers. If you have a conflict between a class name and a namespace, for example, you can use the global keyword to access the namespace:

namespace MyApp
{
    public static class System
    {
        public static void Main()
        {
            global::System.Console.WriteLine("Hello, World!");
            // if we had just used System.Console.WriteLine, 
            // the compile would think that we referred to a 
            // class named "Console" inside our "System" class.
        }
    }
}

global does not work in the following situation, however, as our System class does not have a namespace:

public static class System
{
    public static void Main()
    {
        global::System.Console.WriteLine("Hello, World!");
        // "System" doesn't have a namespace, so the above
        // would be referring to this class!
    }
}



C# Keywords
abstract as base bool break
byte case catch char checked
class const continue decimal default
delegate do double else enum
event explicit extern false finally
fixed float for foreach goto
if implicit in int interface
internal is lock long namespace
new null object operator out
override params private protected public
readonly ref return sbyte sealed
short sizeof stackalloc static string
struct switch this throw true
try typeof uint ulong unchecked
unsafe ushort using var virtual
void volatile while
Special C# Identifiers (Contextual Keywords)
add alias async await dynamic
get global nameof partial remove
set value when where yield
Contextual Keywords (Used in Queries)
ascending by descending equals from
group in into join let
on orderby select where