Errata

What is the precision of Date? The range is specified in days, but the default value
is specified in time, with a 1 second precision. Which day is default? The range
and default should match in precision.

From your examples, "Empty" is also a keyword. There should be an "Empty keyword"
section between the "vbEmpty" section and the "Nothing keyword" section.

states:

... ByRef is much faster than ByVal.

Page 541, last paragraph states:

In general, ByRef arguments ... within class modules take longer to
perform [than ByVal arguments] ...

A section named "Literal Constants" needs to be added describing how to form literal
strings (Enclosed in "s and embedded "s are represented by "". means nothing.),
date literals (Enclosed in #s. Must look like a date -- but what exactly does THAT
mean?), hexadecimal constants (Preceded by &h and in upper or lower case). The on-
line documentation is rather mute about this. I picked up most of this from
examples. Other language definitions usually mention this quite explicitly. See
chap. 3 of JavaScript, The Definitive Guide, examples in chap. 2 of Programming Perl,
6.1.3.4 of the C language standard, etc.

"On Error 0" should read "On Error GoTo 0"

For: [Public|Private] Const constantname = constantvalue
Read: [Public|Private] Const constantname [As datatype] = constantvalue

Also, modify the rest of this entry to reflect the availability of the "As"
clause.

Add: Date and Date$ do not honour locale settings other than the USA locale.

Workaround 1: DateAdd("d",0,Now)
Workaround 2: Format(Now,"dddddd")

add: End

For: Ends a procedure or a block of code.
Read: Terminates program execution, or ends a procedure or a block of code.

False Keyword

Named Arguments
No

Syntax
False

Description
The False keyword has a value of 0.

Programming Tips & Gotchas
The True keyword has a value of -1.

The first parameter should be a time, not a date

For: The Tristate constant values are TristateTrue, TristateFalse, and
TristateUseDefault
Read: The Tristate constant values are vbTrue, vbFalse and vbUseDefault [See
page 604]

For:

Dim hFile As long
hFile = FreeFile()
Open sFileName For Random as #hFile
Do While Not EOF(1)
Get #1,,myVar
Loop
Close #hFile

Read:

Dim hFile As Long
Dim myVar as String
hFile = FreeFile()
Open sFileName For Binary as #hFile
myVar = Space$(LOF(#hFile)) ' Make room for file
Get #hFile,,myVar
Close #hFile

For: The usefulness of a function ... isn't immediately apparent.
Read: InstrRev is useful for extracting the rightmost substring of a string,
for example, extracting a filename from a pathname:

myFile = Mid$(myPath,InstrRev(myPath,"")+1)

[see page 126]

For: The new controls inherit all the properties of the original control,
including it's size and position
Read: The new controls inherit most of the properties of the original control,
including size and position. The properties not inherited are Index, TabIndex,
and Visible (see below).

For: Any valid file number.
Read: Any valid file number. The file must be open shared.

For: ... a Help button is automatically placed on the MsgBox dialog ...
Read: ... you must include vbMsgBoxHelpButton in the buttons argument ...

Add: vbMsgBoxHelpButton 16384 Help

Partition Function (VB6)

Named Arguments
Yes

Syntax

Partition(number, start, stop, interval)
Number
Use: Required
Data Type: Long ?
Number that you want to evaluate against the ranges.


start
Use : Required
Data Type: Long ?
Start of the first range.
stop
Use: Required
Data Type: Long ?
End of the last range.
interval

Use: Required

Data Type: Long ?
Width of each range.


Return Value

A Variant of subtype String indicating where number
occurs within a series of ranges.


Description

The Partition function identifies the particular range
(within a series of ranges) in which the number argument
falls. The start and stop arguments specify the overall
range of numbers, which is split up into smaller ranges
as specified by the interval argument. The Partition function
returns a string representation of the smaller range in which
the number can be found, such as " 1: 10" for a number that
falls in the range of 1 to 10.


Rules at a Glance

* 0 <= start < end.

* 0<interval.

* Any non-integer argument is rounded to the nearest
integer (if the decimal portion is .5 it is rounded to the nearest
even integer).

* If any argument is Null, Partition returns a Null.

* If any argument is invalid, run-time error 5 is
raised (Invalid procedure call or argument).


Example

Consider the following frequency histogram generated by the
Phoenix system, a planning system that fights simulated forest
fires. Source: http://eksl-www.cs.umass.edu/eis/pages/techniques/
histogram-const-desc.html

The code to find the range (or "bin") for an area burned of
47 acres is:

Partition (47,0,100,10)
The result is:
" 40: 49" [ignore the double quotes, but notice the spaces]

Note that:
Partition (47,0,90,10)
Returns:
"40:49" rather than " 40: 49".

Programming Tips & Gotchas

* Partition returns a range with enough leading
spaces so that there are the same number of characters to
the left and right of the colon as there are characters in
stop, plus one. This ensures that if you use Partition with
other numbers, the resulting text will be handled properly
during any subsequent sort operation.

* If interval is 1, the range returned is
number:number, regardless of the start and stop arguments.
For example, if interval is 1, number is 100 and stop is 1000,
Partition returns " 100: 100".

* The following table shows how the ranges are
determined using three sets of start, stop, and interval parts.
The First Range and Last Range columns show what Partition
returns. The ranges are represented by lowervalue:uppervalue,
where the low end (lowervalue) of the range is separated from
the high end (uppervalue) of the range with a colon (:).

Returned results:-


start

stop

interval
number Before First Range
number Within First Range
number Within Last Range
number After Last Range

0
99
5
" :-1"
" 0: 4"
" 95: 99"
" 100: "

20
199
10
" : 19"
" 20: 29"
" 190: 199"
" 200: "

100
1010
20
" : 99"
" 100: 119"
" 1000: 1010"
" 1011: "

In the table above, the last line shows the result when start and stop define
a set of numbers that can't be evenly divided by interval. The last range
extends to stop (11 numbers) even though interval is 20.

For: 0 indicates that payments are due at the beginning of the payment period;
Read: 1 indicates that payments are due at the beginning of the payment period;

For: 1 indicates that payments are due at the end of the period.
Read: 0 indicates that payments are due at the end of the period.

For: A Double representing the monthly payment.
Read: A Double representing the periodic payment for an annuity.

Add: Outputs a closed circle, elipse or pie slice (arc with radius lines drawn
at both ends).
Syntax: Circle oPrinter.Circle [Step] (x,y), radius, [color, start, end,
aspect]

For: Syntax: oPrinter.Line [Step] (x1,1) [Step] (x2,y2) [color], [B][F]
Read: Syntax: oPrinter.Line [Step] (x1,y1) [-] [Step] (x2,y2) [color], [B][F]

Add: Outputs the evaluated output list
Syntax: oPrinter.Print [outputlist]
Example: oPrinter.Print "Printout finished at " ; Time()

subsection:
For: ... in pixels ...
Read: ... in scale units ...

sample code:
Add: Dim oPrinter as Printer

For: ... negative number as an argument immediately prior to using Randomize
with any numeric argument.
Read: ... negative number as an argument.

Round with a numdecimalplaces set to 2 is NOT equivalent to Format (expression,
"#.##")!!!

THIS IS VERY IMPORTANT IN FINANCIAL APPLICATIONS!!!

Round() and Format() round numbers differently when the digit to the right of
numdecimalplaces is a 5. Format will always round this number up and Round() will
round up or down depending on whether the numdecimalplaces digit is even or odd!!!!!!

Ex. [Even digit - NOT EQUIVALENT!!]
Format(23.685,"#.##") = 23.69
Round(23.685,2) = 23.68
-----------------------------------
[Odd digit - Equivalent]
Format(23.675,"#.##") = 23.68
Round(23.675,2) = 23.68

In financial apps I use CCur(Format(myNumber,"#.##")) which is clumsy but correct.

For: ... between 0 and 16.
Read: ... between 0 and 22.

For: ... numdecimalplaces is 5 or greater ...
Read: ... numdecimalplaces is 6 or greater ...

For: ... incremented by 1; otherwise ...
Read: ... incremented by 1; if 5, the number is adjusted to be the nearest
even integer; otherwise ...

Add: Boolean False

For: stdDataFormats Events
Read: stdDataFormat Events

For: Halts program execution.
Read: Pauses program execution.

True Keyword

Named Arguments
No

Syntax
True

Description
The True keyword has a value of -1.

Programming Tips & Gotchas
The False keyword has a value of 0.

For: Any valid file number.
Read: Any valid file number. The file must be open shared.

For: 10111100 = 00001111 Imp 10110011
Read: 10111100 = 00001111 Xor 10110011


INDEX: