Delphi Language Guide Delphi for Microsoft Win32 Delphi for the Microsoft. Net framework

Character Strings
A character string, also called a string literal or string constant, consists of a quoted string, a control string, or a
combination of quoted and control strings. Separators can occur only within quoted strings.
A quoted string is a sequence of up to 255 characters from the extended ASCII character set, written on one line
and enclosed by apostrophes. A quoted string with nothing between the apostrophes is a null string. Two sequential
apostrophes in a quoted string denote a single character, namely an apostrophe. For example,
28

---

'BORLAND' { BORLAND }
'You''ll see' { You'll see }
''''          { ' }
''            { null string }
' '           { a space }
A control string is a sequence of one or more control characters, each of which consists of the # symbol followed by
an unsigned integer constant from 0 to 255 (decimal or hexadecimal) and denotes the corresponding ASCII
character. The control string
#89#111#117
is equivalent to the quoted string
'You'
You can combine quoted strings with control strings to form larger character strings. For example, you could use
'Line 1'#13#10'Line 2'
to put a carriage-returnline-feed between 'Line 1' and 'Line 2'. However, you cannot concatenate two quoted strings
in this way, since a pair of sequential apostrophes is interpreted as a single character. (To concatenate quoted
strings, use the + operator or simply combine them into a single quoted string.)
A character string's length is the number of characters in the string. A character string of any length is compatible
with any string type and with the PChar type. A character string of length 1 is compatible with any character type,
and, when extended syntax is enabled (with compiler directive 
{$X+}
), a nonempty character string of length n is
compatible with zero-based arrays and packed arrays of n characters. For more information, see Datatypes,
Variables, and Constants.