Computer Programming Concepts and Visual Basic David I. Schneider

428 Computer Programming Concepts and Visual Basic
CVAR The function CVar converts strings and byte, integer, long integer, single-precision~,
double-precision, and currency numbers to variants. If x is any string or number, the value of
CVar(x) is the variant determined by x. [variant]
CVDATE The function CVDate converts a numeric or string expression to an equivalent serial
date. If x is any expression representing a valid date, the value of CVDate(x) is the serial
date determined by x. Valid numeric values are –657434 (January 1, 100 AD.) to 2958465
(December 31, 9999). Valid string expressions either look like one of these valid numeric
values (for example, “19497”corresponding to May 18, 1953) or look like a date (for example,
“10 Feb 1955”, “August 13, 1958”, etc.) [date]
DATABASENAME The value of the DatabaseName property of a data control is the filespec
of the file containing the database.
DATAFIELD After the DataSource property of a data-aware control has been set to bind the
control to a data control, the DataField property is set to a field of the table accessed by the
data control.
DATASOURCE To bind a data-aware control to a data control at design time, set the value
of the DataSource property of the data-aware control to the name of the data control.
DATE The value of the function Date is the current date. If dateStr is a string representing
a date, the statement Date = dateStr changes the date as specified by dateStr.
DATE A variable of type Date requires 8 bytes of memory and holds numbers representing
dates from January 1, 100 to December 31, 9999. Literal date values can be assigned to date
variables with statements such as dateVar = #5/12/1999#, dateVar = #5 Jan, 1997#, and dateVar
= #February 10, 2004#. However, values of dateVar are displayed in the form
month/day/year (for example, 5/12/99).
DATESERIAL The value of the function DateSerial(year, month, day) is the serial date corresponding
to the given year, month, and day. Values from 0 to 9999 are acceptable for year,
with 0 to 99 interpreted as 1900 to 1999. Values of 1 to 12 for month, and 1 to 31 for day are
normal, but any integer value is acceptable. Often, numeric expressions are used for month
or day that evaluate to numbers outside these ranges. For example, DateSerial(1993, 2, 10 +
90) is the date 90 days after Feb. 10, 1993. [date]
DATEVALUE The value of the function DateValue(str) is the serial date corresponding to
the date given in str. DateValue recognizes the following date formats: “2-10-1955”,
“2/10/1955”, “February 10, 1955”, “Feb 10, 1955”, “10-Feb-1955”, and “10 February 1955”.
For the years 1900 through 1999, the initial “19”is optional. [date]
DAY The function Day extracts the day of the month from a serial date. If d is any valid serial
date, the value of Day(d) is an integer from 1 to 31 giving the day of the month recorded
as part of the date and time stored in d. [date]
DBLCLICK The DblClick event applies to combo boxes, file list boxes, forms, frames,
grids, images, labels, list boxes, OLE controls, option buttons, picture boxes, and text boxes.
A DblClick event occurs whenever the left mouse button is pressed and released twice, in
quick succession, while the mouse cursor is over the control or over a blank area on the form.
Double-clicking on an object will first cause that object’s Click event to occur, followed by
its DblClick event. Note: When you double-click on an item in a drive list box, the item is
automatically assigned to the Path property. When you double-click on an item in a file list
box, the item is automatically assigned to the FileName property.
DEFAULT When the Default property of a command button is set to True and the focus is
on an object that is not another command button, pressing the enter key has the same effect
as clicking on the button. At most, one command button on a form can have True as the value
of its Default property.