What's the @ in front of a string in C#?

Question

This is a .NET question for C# (or possibly VB.net), but I am trying to figure out what's the difference between the following declarations:

string hello = "hello"; 

vs.

string hello_alias = @"hello"; 

Printing out on the console makes no difference, the length properties are the same.

Answer 1

It marks the string as a verbatim string literal - anything in the string that would normally be interpreted as an escape sequence is ignored.

So "C:\\Users\\Rich" is the same as @"C:\Users\Rich"

There is one exception: an escape sequence is needed for the double quote. To escape a double quote, you need to put two double quotes in a row. For instance, @"""" evaluates to ".

Answer 2

It's a verbatim string literal. It means that escaping isn't applied. For instance:

string verbatim = @"foo\bar"; string regular = "foo\\bar"; 

Here verbatim and regular have the same contents.

It also allows multi-line contents - which can be very handy for SQL:

string select = @" SELECT Foo FROM Bar WHERE Name='Baz'"; 

The one bit of escaping which is necessary for verbatim string literals is to get a double quote (") which you do by doubling it:

string verbatim = @"He said, ""Would you like some coffee?"" and left."; string regular = "He said, \"Would you like some coffee?\" and left.";