Computer Programming Concepts and Visual Basic David I. Schneider

yields “1234.”, Format(1234000, “#,,.0”) yields “1.2”, and Format(1234000, “#,0,.0”) yields
“1,234.0”.
The percent symbol (%) placed to the right of all #’s, 0’s, and any decimal point causes
the number to be converted to a percentage (multiplied by 100) before formatting and the
symbol % to be displayed. For example, Format(.05624, “#.##%”) yields “5.62%”, and Format(1.23,
“#%”) yields “123%”.
The symbols E+ and E– placed to the right of all #’s, 0’s, and any decimal point cause
the number to be displayed in scientific notation. Places for the digits in the exponent must
be reserved to the right of E+ or E– with #’s or 0’s. When E+ is used and the exponent is positive,
a plus sign appears in front of the exponent in the result. When E– is used and the exponent
is positive, no sign or space precedes the exponent. When scientific notation is used,
each position reserved by #’s to the left of the decimal point is used whenever possible. For
example, Format(1234.56, “#.##E+##”) yields “1.23E+3”, Format(1234.56, “##.##E–##”)
yields “12.34E2”, Format(1234, “###.00E+##”) yields “123.40E+1”, and Format(123,
“###E+00”) yields “123E+00”.
Date and time output can be formatted using numbers or names for months, putting the
day, month, and year in any order desired, using 12-hour or 24-hour notation, and so on. This
is accomplished either by letting str be the name of one of several predefined date/time formats
or by combining in str one or more special date/time formatting characters. The expression
to be formatted can evaluate to a number that falls within the range of valid serial dates
or to a string representing a date/time.
Predefined date/time formats include “General Date,” which displays a date in
mm/dd/yyyy format and, if appropriate, a time in hh:mm:ss PM format; “Long Date,”which
displays the day of week, the full name of month, the day, and a four-digit year; “Medium
Date,”which displays the day, abbreviated month name, and two-digit year; “Short
Date,”which displays “mm/dd/yy”; “Long Time,”which displays the time in hh:mm:ss PM
format; “Medium Time,”which displays time in hh:mm PM format; and “Short Time,”which
display time in 24-hour format as hh:mm. For example, let dt = DateSerial(55,2,10) +
Time~Serial(21,45,30). Then Format(dt, “General Date”) yields “2/10/55 9:45:30 PM”, Format(dt,
“Medium Date”) yields “10-Feb-55”, and Format(dt, “Short Time”) yields “21:45”.
Format symbols for the day, month, and year include d (day as number but no leading
zero), dd (day as number with leading zero), ddd (day as three-letter name), dddd (day as full
name), m (month as number but no leading zero), mm (month as number with leading zero),
mmm (month as three-letter name), mmmm (month as full name), yy (year as two-digit number),
and yyyy (year as four-digit number). Separators such as slash, dash, and period may
be used as desired to connect day, month, and year symbols into a final format. For example,
Format(“August 13, 1958”, “dddd, d.mmm.yy”) yields “Wednesday, 13.Aug.58” and Format(“July
4, 1776”, “ddd: mmmm dd, yyyy”) yields “Thu: July 04, 1776”. Additional format
symbols for dates include w (day-of-week as number 1–7), ww (week-of-year as number
1–53), q (quarter-of-year as number 1–4), y (day-of-year as number 1–366), ddddd (same as
short date), and dddddd (same as long date).
Format symbols for the second, minute, and hour include s (seconds with no leading
zero), ss (seconds as two-digit number), n (minutes with no leading zero), nn (minutes as
two-digit number), h (hours with no leading zero), hh (hours as two-digit number), AM/PM
(use 12-hour clock and uppercase), am/pm (use 12-hour clock and lowercase), A/P (use 12hour
clock and single uppercase letter), a/p (use 12-hour clock and single lowercase letter),
and ttttt (same as general date). Separators such as colons and periods may be used as desired
to connect hour, minute, and second symbols into a final format. For example, Format(“14:04:01”,
“h:nn AM/PM”) yields “2:04 PM”, Format(“14:04:01”, “h.n.s”) yields
“14.4.1”, and Format(0.75, “h:nna/p”) yields “6:00p”.
String output can be formatted as all uppercase, all lowercase, left-justified or right-justified.
Symbols used to format strings are @ (define a field for at least as many characters
as there are @ symbols; if less characters than @ symbols, fill remainder of field with
spaces; if more characters than @ symbols, display the extra characters—don’t clip), &
(reserve space for entire output string), < (convert all characters to lowercase before dis-
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