Use the Long Reserved Word as a Variable Name in C#

Use the long reserved word as a variable name in C#

Yes, you can if you really want to:

private string @long;

The actual name of the variable (as reported by reflection etc) is just long; the @ sign tells the compiler to ignore the fact that it's also a keyword.

I would very strongly advise against this, however.

How do I use a C# reserved keyword as a property name without the @ prefix?

You can't. It is a reserved keyword. That means "you can't". Contrast to "contextual keywords" which usually means "we added this later, so we needed it to work in some pre-existing scenarios".

The moderate answer here is: use @return.

A better answer here is: rename your property. Perhaps ReturnValue.

There is also the option of, say, Return - but you might need to think about case-insensitive languages too.

Deserializing url-encoded-form-data with reserved word as variable name

The trick is to tell the compiler to not treat that name as the reserved keyword event, and you do that with an at-sign, like this:

public string @event { get; set; }

Now, you might think this will be similar to using an underscore but that is not correct. The at-sign will actually not become part of the event name, it's just there to tell the compiler to not treat the next word as a reserved keyword, and instead treat it as an identifier.

Also note that everywhere you want to refer to this property, you likely have to keep using the at-sign prefix or that reference will not compile either.

Here's an example:

void Main()
{
    Console.WriteLine(nameof(@event));
    Console.WriteLine(nameof(_event));
}

public string @event { get; set; }
public string _event { get; set; }

Will output:

event
_event

C# keywords as a variable

string @string = "";

How do I use a C# keyword as a property name?

You can use keywords in C# as identifiers by prepending @ infront of them.

var @class = new object();

To quote from the MSDN Documentation on C# Keywords:

Keywords are predefined, reserved identifiers that have special
meanings to the compiler. They cannot be used as identifiers in your
program unless they include @ as a prefix. For example, @if is a valid
identifier but if is not because if is a keyword.

Reserved words as names or identifiers

No, there is no way. That's why they're labeled "reserved".

How do I use a Javascript keyword as a variable name?

Well, if you insist, you can

var $break = 1;

which is the same as C# in terms of characters ;)

Seriously, you cannot use reserved keywords as variables, but they are allowed as property names:

myObj = {}
myObj.break = 'whatever';

Also, do note that the repertoire of the reserved words varies depending on the strictness. For example,

var interface = 1;

is valid in the non-strict mode, but breaks once you add use strict to your script.

What does placing a @ in front of a C# variable name do?

It's just a way to allow declaring reserved keywords as vars.

void Foo(int @string)

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