@-quoted string literals start with @ and are also enclosed in double quotation marks. For example:
@"good morning" // a string literal
The advantage of @-quoting is that escape sequences are not processed, which makes it easy to write, for example, a fully qualified file name:
@"c:\Docs\Source\a.txt" // rather than "c:\\Docs\\Source\\a.txt"
To include a double quotation mark in an @-quoted string, double it:
@"""Ahoy!"" cried the captain." // "Ahoy!" cried the captain.