Sections
Introduction
Variables
Base Types
Prefixes
Qualifiers
Examples

Tables
1: Prefix, base, and qualifier examples

2: Standard Variable Bases

3: Standard Control
Bases

4: Standard DAO
Bases

5: Standard Variable Prefixes

6: Standard Variable Qualifiers

7: Examples

Quick Reference
Tables on 1 page
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Hungarian Notation

Introduction

This document details standard Hungarian notation. This discussion of Hungarian differs from other Hungarian notation outlines in that the types have been assigned with both Visual Basic and C/C++ in mind. The intention is to supply a notation encompassing both languages.

Hungarian notation can be used to reduce variable ambiguity and increase code clarity. While it can be argued that the use of Hungarian notation under C/C++ is an individual preference, under Visual Basic a naming convention can help avoid a syntactic ambiguity. C/C++ member function calls and member variable access can be differentiated by the existence of parenthesis for member function calls, however, this is not true in Visual Basic. Access to user defined type members is syntactically indistinguishable from access to control properties without using a naming convention.

Engineers are not limited to the types provided. However, new types should not conflict with the standard notation. In addition, strict adherence to the base types is not required, but recommended. Although consistency is the key for Hungarian notation, deviations from the standard base types must be consistent throughout. For example, historically, some languages used "i" and "j" as default integer variables. Many engineers use "i" as a nondescript loop counter even though this deviates from the standard notation. If used consistently, this deviation is acceptable.

Variables

All variable names are composed of three elements: prefixes, base type, and qualifier. The base type is required while the prefixes and qualifiers are optional. The base type is a mnemonic used to identify the variable type. In cases where the base type is not specific enough to identify the variable type or to specify variable scope, prefix mnemonics should be used. The qualifier is used to distinguish variables of the same type. A qualifier is a word or text fragment descriptive of the variable’s intended function.

Table 1: Prefix, base, and qualifier examples

Variable	Prefix	Base	Qualifier
nTotal	prefix is omitted indicating a variable of local scope.	n is the base indicating an integer.	Total is the qualifier.
gkMegabyte	g is the prefix indicating a variable of global scope.	k is the base indicating a constant.	Megabyte is the qualifier.
s	prefix is omitted indicating a variable of local scope.	s is the base indicating a string.	qualifier is omitted indicating a temporary or multi-use variable.

Base Types

The base type is a mnemonic used to identify the variable type. The standard base types for intrinsic data types are given in the table below. Engineers may create their own base types if required. However, new base types should not conflict with the standard base types.

The standard base types have been assigned with both Visual Basic and C/C++ in mind. Data types available in both languages have been given the same base type whenever possible regardless of actual data implementation sizes. The Visual Basic base type table contains the default suffix for informational purposes only. Our software standards for Visual Basic requires explicit variable declaration.

Table 2: Standard Variable Bases

Base	Data Type	C/C++	Visual Basic	VB Suffix
b	byte	unsigned char b;	dim b as string * 1 OR dim b as byte
c	char	char c;	dim c as string * 1
col	collection		dim col as new Collection
cur	currency		dim cur as currency	@
d	double	double d;	dim d as double	#
e	float, single	float e;	dim e as single	!
f	flag (boolean or logical)	int f;	dim f as integer OR dim f as boolean
fn	function
h	handle	HWND hwnd;	dim hwnd as integer
k	constant (#defines, enums, const)	#define k = 2	const k = 2
l	long	long l;	dim l as long	&
ld	long double	long double ld;
n	int, short, integer	int i; short i;	dim n as integer	%
o	object	Object o;	dim o as new Object
s	string		dim s as string	$
sz	null terminated string	char sz[10];	dim sz as string
t	user defined type (structure, typedef, type)	UserType t;	dim t as UserType
uc	unsigned char	unsigned char uc;	dim uc as string * 1
ul	unsigned long	unsigned long ul;
un	unsigned int	unsigned int un;
v or vd	void	void *v;
v or vnt	variant		dim v as variant
w	word	WORD w;	dim w as integer

Table 3: Standard Control Bases, new items are in bold

Base	Control Type	Base	Control Type
ani	Animation	mhint	Microhelp Integer Edit
bed	Pen Bedit	mhlst	Microhelp 3D Listbox
brw	VB5 WebBrowser	mhrel	Microhelp Real Edit
cbo	Combobox and dropdown Listbox	mnu	Menu
chk	Checkbox	mpm	MAPI Message
cht	VB5 MS Chart	mps	MAPI Session
clp	Picture Clip	ole	Ole Client
cmd	Command Button	opt	Option Button
com	Communications	out	Outline Control
ctl	Control (specific type is unknown)	pic	Picture
dat	Data	pnl	3d Panel (threed)
dbcbo	Apex DbCombo	prg	VB5 ProgressBar
dbg	Apex DbGrid	rdc	VB5 Remote Data Control
dir	Directory List Box	rpt	Report Control
dlg	Common Dialog	rtx	VB5 RichText
drv	Drive List Box	sb	VB5 Statusbar
eas	Lassalle EasyNet drawing control	shp	Shape (circle, square, oval, ...)
els	Videosoft Elastic	sld	VB5 Slider
fil	File List Box	spn	Spin Control
fpb	Farpoint fpBoolean	sstb	SS Tab
fpc	Farpoint fpCurrency	sys	VB5 SysInfo
fpds	Farpoint fpDoubleSingle	tb	VB5 toolbar
fpdt	Farpoint fpDateTime	tbr	Cockell Toolbar
fpli	Farpoint fpLongInteger	tbs	VB5 Tabstrip
fpm	Farpoint fpMemo	tdbg	Apex TrueDbGrid
fpmsk	Farpoint fpMask	tgrd	Apex Truegrid
fptxt	Farpoint fpText	tip	Cockell ToolTip
fra	Frame	tlst	Bennett-Tec Tlist hierarchical listbox
frm	Form	tmr	Timer
gau	Gauge	tnm	Text Numeric (textBox)
gpb	Group Push Button	tv	VB5 TreeView
gra	Graphic Server Graph	txt	Text/Edit Box
grd	Grid	upd	VB5 UpDown
hed	Pen Hedit	vcf	Visual Components F1Book
hsb	Horizontal Scroll Bar	vcg	Visual Components vtChart
img	Image	vfa	Videosoft vsFlexArray
iml	VB5 ImageList	vfs	Videosoft vsFlexString
ink	Pen Ink	vsb	Vertical Scroll Bar
itb	Videosoft Index tab	vsd	Videosoft vsDraw
itc	VB5 Internet Transfer (Inet)	vsi	Videosoft vsInForm
key	Keyboard key status	vsp	Videosoft vsPrinter
lbl	Label	vsr	Videosoft vsReport
lin	Line	vsv	Videosoft vsViewPort
lst	Listbox	wsk	VB5 Winsock
lv	VB5 ListView
mci	MCI
med	Masked Edit
mhdat	MicroHelp Date Edit

Table 4: Standard Data Access Object (DAO) Bases

Base	DAO Type	Base	DAO Type
con	Container	prm	Parameter
db	Database	qry	QueryDef
dbe	DBEngine	rec	Recordset
doc	Document	rel	Relation
ds	Dynaset	tbd	TableDef or Table
fld	Field	usr	User
grp	Group	wsp	Workspace
idx	Index

Prefixes

In cases where the base type is not specific enough to identify the variable type or to specify variable scope, prefix mnemonics should be used.

Table 5: Standard Variable Prefixes

Prefix	Definition	C/C++	Visual Basic
g	global scope	Yes	Yes
m	module/form global or static	Yes	Yes
p	pointer	Yes
lp	long pointer	Yes
hp	huge pointer	Yes
i	index into an array	Yes	Yes
a	array	Yes	Yes

The array prefix (a) is most often used when accessing an array with a pointer, ie. paszNames is a pointer to an array of null terminated strings. Often the array prefix is omitted when not using a pointer, ie. gtModel(0).sName = "Hello" is a reference to a global array of some user defined type. The element subscript access (0) can be sufficient.

Qualifiers

The qualifier is used to distinguish variable of the same type. A qualifier is a word or text fragment descriptive of the variable’s intended function. The qualifier should use mixed case or underscores within itself and to separate itself from the base.

Table 6: Standard Variable Qualifiers

Qualifier	Definition
First	first element to deal with in a set
Last	last element to deal with in a set
Lim	upper limit of a set, an invalid element; equal to Last + 1
Min	first element in a set
Max	last element in a set
Sav or Tmp	temporary value
Nil	illegal value
Null	zero
Src	a source
Dst	a destination
Data	general purpose item

Examples

The following table contains examples of Hungarian notation.

Table 7: Hungarian Notation Examples

Variable	Definition
nTotal	integer named Total
szTitle	null terminated string named Title
sResults	string named Results
pcSelectChar	pointer to character named SelectChar
anValues or nValues(i)	array of integers named Values
tCar	structure named Car
atCar or tCar(i)	array of structures named Car
iCurCar	array index named CurCar
gkMegabyte	global constant named Megabyte
mnSelected	module/form global or static integer named Selected
lpfnTask	long pointer to a function named Task
hWnd	handle named Wnd
eSum	float or single named Sum
fState	flag (boolean or logical) named State
gksSection	global constant string named Section
dValue	double named Value
vSrc	a variant named Src that indicates a source by using a standard qualifier
vDst	a variant named Src that indicates a destination by using a standard qualifier