Valid characters for GraphicString and ISO646String

Table 1. Valid characters for GraphicString and ISO646String
Character name	Glyph
Uppercase letters	A-Z
Lowercase letters	a-z
Digits	0-9
Space
Exclamation mark	!
Quotation mark	'
Number sign	#
Dollar sign	$
Percent sign	%
Ampersand	&
Apostrophe	'
Left parenthesis	(
Right parenthesis	)
Asterisk	*
Plus sign	+
Comma	,
Hyphen	-
Full stop	.
Solidus	/
Colon	:
Semicolon	;
Less than sign	<
Equals sign	=
Greater than sign	>
Question mark	?
Commercial at	@
Left square bracket	[
Reverse solidus	\
Right square bracket	]
Upward arrow head	^
Underline	_
Grave accent	ˋ
Left curly bracket	{
Vertical line	\|
Right curly bracket	}
Overline	‾

Composite graphics, which are those constructed with backspaces in a GraphicString, are not allowed.

If a character that is not valid is entered on encoding, the string is rejected and an error code is returned to the application program. On decoding, characters that are not valid are accepted and translated to periods.