Visual Basic Functions Syntax
Visual Basic provides more
than 200 built-in statements and functions. Some are used frequently;
some are seldom used at all. Even experienced programmers sometimes happen
upon a statement or function they didn't know about.
This appendix can be considered
a quick-reference guide to all of VB's built-in statements and functions.
It offers the syntax for each, as well as a brief description of what
it does and how its arguments (if any) are used. This is by no means a
complete reference. Microsoft's Visual Basic 6.0 Language Reference
is probably the best source for in-depth information on VB's statements
and functions. If you have any questions about syntax or use of a particular
statement or function, then you are strongly urged to consult that reference
to obtain additional information.
Functions
and Statements
Abs
Function
Abs(number)
Returns the absolute value
of number. The data type returned is the same as the data type
of the number argument.
AppActivate
Statement
AppActivate title[,wait]
Activates the application window
that has the string title in its title bar or, alternatively, the
task ID specified by title. The optional wait argument (Boolean)
can be used to specify whether the calling application should wait until
it has the focus before the application window is activated.
Array
Function
Array(arglist)
Returns a Variant data item
that contains an array. arglist refers to a comma-delimited list
of values that make up the elements of the array, with the first value
corresponding to the first element of the array, the second value corresponding
to the second element of the array, and so on.
Asc
Function
Asc(string)
Returns an Integer value that
represents the ASCII code for the first character in the string.
Atn
Function
Atn(number)
Returns a Double value that
is the arctangent of number.
Beep
Statement
Beep
Sounds a tone through the PC's
speaker. Frequency and duration of the tone may vary from system to system.
Call
Statement
[Call] name [argumentlist]
Executes a sub, function, or
DLL procedure. The name argument specifies the name of the procedure
to call, and argumentlist is an optional list of arguments that
will be passed to the called procedure. The Call keyword is optional,
but if it is included, then at least one or more arguments for argumentlist
must also be included.
CBool
Function
CBool(expression)
Converts the value of expression
to a Boolean data type. The argument expression can be any valid
string or numeric expression.
CByte
Function
CByte(expression)
Converts the value of expression
to a Byte data type. The argument expression must be a numeric
value between 0 and 255.
CCur
Function
CCur(expression)
Converts the value of expression
to a Currency data type. The argument expression must be a numeric
value between -922,337,203,685,477.5808 and 922,337,203,685,477.5807.
CDate
Function
CDate(expression)
Converts the value of expression
to a Date data type. The argument expression must be a valid date
expression.
CDbl
Function
CDbl(expression)
Converts the value of expression
to a Double data type. The argument expression must be a numeric
value between -1.79769313486232E308 and -4.94065645841247E-324 for negative
values, or between 4.94065645841247E-324 and 1.79769313486232E308 for
positive values.
CDec
Function
CDec(expression)
Converts the value of expression
to a Decimal data type. The argument expression must be a numeric
value of +/-79,228,162,514,264,337,593,543,950,335 for zero-scaled numbers
(numbers with no decimal places), or +/-7.9228162514264337593543950335
for numbers with 28 decimal places.
ChDir
Statement
ChDir path
Changes the current directory
to the one specified by the path argument. Note that although ChDir
changes the default directory, it does not change the default drive as
well.
ChDrive
Statement
ChDrive drive
Changes the current drive to
the one specified by the drive argument.
Choose
Function
Choose(index, choice-1[, choice-2, ... [, choice-n]])
Returns a value from a list
of choices (specified by the arguments choice-1 through choice-n)
based on the value of the index argument. If index is 1,
then the value returned by the Choose function will be the value represented
by choice-1; if index is 2, then the value returned will
be that of choice-2; and so on.
Chr
Function
Chr(charcode)
Returns a one-character String
value that represents the ASCII character of the number specified by the
charcode argument.
CInt
Function
CInt(expression)
Converts the value of expression
to an Integer data type. The argument expression must be a numeric
value from -32,768 to 32,767. Fractions are rounded.
CLng
Function
CLng(expression)
Converts the value of expression
to a Long data type. The argument expression must be a numeric
value from -2,147,483,648 to 2,147,483,647. Fractions are rounded.
Close
Statement
Close [filenumberlist]
Closes any files opened with
the Open statement that corre- spond to the file numbers specified by
filenumberlist. The filenumberlist argument can contain
a single file number (for example, #1) or multiple file numbers (for example,
#1, #4, #5). If the filenumberlist argument is omitted, all open
files will be closed.
Command
Function
Command
Returns any command-line arguments
specified when launching Visual Basic. For compiled programs, Command
returns the command-line arguments specified when the program was launched.
Const
Statement
[Public | Private] Const constname [As type] = expression
Declares a constant with the
name constname and the value represented by expression.
The Public and Private keywords define the constant's scope, and the optional
As type specifies the constant's data type. If the As type
is omitted, the constant will be declared as the data type most appropriate
for expression.
Cos
Function
Cos(number)
Returns a Double value that
is the cosine of the angle specified by the number argument.
CreateObject
Function
CreateObject(class)
Creates and returns a reference
to an ActiveX object of type class. The class argument should
use the syntax appname.objecttype, where appname is the
name of the application providing the object, and objecttype is
the class of the object to be created.
CSng
Function
CSng(expression)
Converts the value of expression
to a Single data type. The argument expression must be a numeric
value from -3.402823E38 to -1.401298E-45 for negative values, or from
1.401298E-45 to 3.402823E38 for positive values.
CStr
Function
CStr(expression)
Converts the value of expression
to a String data type. The string that CStr returns depends on the data
type of the expression argument: For Booleans, CStr returns either
True or False; for Dates, CStr returns a date based on the short date
format on your system; for Errors, CStr returns the word Error followed
by the error number. expression values that are Empty return a
zero-length string, and numeric expression values return a string
containing the number. A Null expression value will cause a runtime
error.
CurDir
Function
CurDir[(drive)]
Returns a String value that
represents the full path of the current directory. If the drive
argument is given, then CurDir returns the directory path of the current
directory for that drive.
CVar
Function
CVar(expression)
Converts the value of expression
to a Variant data type. The argument expression can be either numeric
or a string.
CVErr
Function
CVErr(errornumber)
Returns a Variant of subtype
Error that contains the error number specified by the errornumber
argument.
Date
Function
Date
Returns a Variant of subtype
Date that contains the current system date.
Date
Statement
Date = date
Sets the current system date
as specified by the date argument. For Windows 95 systems, date
must be a valid date between January 1, 1980 and December 31, 2099. For
Windows NT systems, date must be a valid date between January 1,
1980 and December 31, 2079.
DateAdd
Function
DateAdd(interval, number, date)
Returns a Variant of subtype
Date calculated by taking the date specified by the date argument
and adding or subtracting the amount of time specified by interval
and time. The interval argument contains a code that represents
a unit of time (for example, yyyy for years, m for months,
d for days), and number is the number of units to be added
to date.
DateDiff
Function
DateDiff(interval, date1, date2[,firstdayofweek[, firstweekofyear]])
Returns a Variant of subtype
Long that represents the number of time units between two dates (date1
and date2). The interval argument contains a code that represents
the unit of time (for example, yyyy for years) that will be returned
by the function. The optional firstdayofweek and firstweekofyear
arguments are used to specify how the time difference should be calculated
when certain codes are used for interval.
DatePart
Function
DatePart(interval, date[,firstdayofweek[,firstweekofyear]])
Returns a Variant of subtype
Integer that contains the part of date specified by interval.
The interval argument contains a code that represents the unit
of time (for example, ww for weeks) that will be returned by the
function. The optional firstdayofweek and firstweekofyear
arguments are used to specify how the date should be calculated when certain
interval codes are used.
DateSerial
Function
DateSerial(year, month, day)
Returns a Variant of subtype
Date that represents a date as specified by the year, month,
and day arguments.
DateValue
Function
DateValue(date)
Returns a Variant of subtype
Date that is derived from the date value specified by the date
argument.
Day
Function
Day(date)
Returns a Variant of subtype
Integer that represents the day of the month (1[nd]31) for the date value
specified by the date argument.
DDB
Function
DDB(cost, salvage, life, period[, factor])
Returns a Double value that
represents the depreciation of an asset for a specified amount of time
using a given method of depreciation. The cost argument represents
the initial cost of the asset, salvage represents the value of
the asset at the end of its working lifetime, life represents the
lifetime of the asset, and period represents the period (in months)
for which the depreciation is calculated. The optional factor argument
specifies the rate at which the balance declines. If it is omitted, then
the double-declining depreciation method is used.
Declare
Statement
[Public | Private] Declare Sub name Lib "libname" [Alias _ "aliasname"][([arglist])]
or
[Public | Private] Declare Function name Lib "libname"
[Alias "aliasname"][([arglist])][As type]
Declares references to Sub
or Function procedures in an external DLL (dynamic-link library). The
optional Public and Private keywords define the procedure's scope. The
name argument is the name of the procedure, and the libname
argument specifies the DLL that contains the procedure. The optional aliasname
argument specifies an alternate name for the procedure in the DLL. arglist
is a list of arguments passed to the procedure. For Function procedures,
the As type specifies the data type of the value returned by the
Function. Declare statements can only be used at module level.
DefBool
Statement
DefBool letterrange[, letterrange]...
Specifies that all variables
and function return values that begin with the letters specified by the
letterrange arguments are automatically defined to be of the Boolean
data type. The letterrange arguments should be constructed as letter1[-letter2],
where letter1 is the first (or only) letter in the range, and letter2
is the last letter in the range. DefBool can only be used at module level.
DefByte
Statement
DefByte letterrange[, letterrange]...
Specifies that all variables
and function return values that begin with the letters specified by the
letterrange arguments are automatically defined to be of the Byte
data type. The letterrange arguments should be constructed as letter1[-letter2],
where letter1 is the first (or only) letter in the range, and letter2
is the last letter in the range. DefByte can only be used at module level.
DefCur
Statement
DefCur letterrange[, letterrange]...
Specifies that all variables
and function return values that begin with the letters specified by the
letterrange arguments are automatically defined to be of the Currency
data type. The letterrange arguments should be constructed as letter1
[-letter2], where letter1 is the first (or only) letter
in the range, and letter2 is the last letter in the range. DefCur
can only be used at module level.
DefDate
Statement
DefDate letterrange[, letterrange]...
Specifies that all variables
and function return values that begin with the letters specified by the
letterrange arguments are automatically defined to be of the Date
data type. The letterrange arguments should be constructed as letter1[-letter2],
where letter1 is the first (or only) letter in the range, and letter2
is the last letter in the range. DefDate can only be used at module level.
DefDbl
Statement
DefDbl letterrange[, letterrange]...
Specifies that all variables
and function return values that begin with the letters specified by the
letterrange arguments are automatically defined to be of the Double
data type. The letterrange arguments should be constructed as letter1[-letter2],
where letter1 is the first (or only) letter in the range, and letter2
is the last letter in the range. DefDbl can only be used at module level.
DefDec
Statement
DefDec letterrange[, letterrange]...
Specifies that all variables
and function return values that begin with the letters specified by the
letterrange arguments are automatically defined to be of the Decimal
data type. The letterrange arguments should be constructed as letter1[-letter2],
where letter1 is the first (or only) letter in the range, and letter2
is the last letter in the range. DefDec can only be used at module level.
DefInt
Statement
DefInt letterrange[, letterrange]...
Specifies that all variables
and function return values that begin with the letters specified by the
letterrange arguments are automatically defined to be of the Integer
data type. The letterrange arguments should be constructed as letter1[-letter2],
where letter1 is the first (or only) letter in the range, and letter2
is the last letter in the range. DefInt can only be used at module level.
DefLng
Statement
DefLng letterrange[, letterrange]...
Specifies that all variables
and function return values that begin with the letters specified by the
letterrange arguments are automatically defined to be of the Long
data type. The letterrange arguments should be constructed as letter1[-letter2],
where letter1 is the first (or only) letter in the range, and letter2
is the last letter in the range. DefLng can only be used at module level.
DefObj
Statement
DefObj letterrange[, letterrange]...
Specifies that all variables
and function return values that begin with the letters specified by the
letterrange arguments are automatically defined to be of the Object
data type. The letterrange arguments should be constructed as letter1[-letter2],
where letter1 is the first (or only) letter in the range, and letter2
is the last letter in the range. DefObj can only be used at module level.
DefSng
Statement
DefSng letterrange[, letterrange]...
Specifies that all variables
and function return values that begin with the letters specified by the
letterrange arguments are automatically defined to be of the Single
data type. The letterrange arguments should be constructed as letter1[-letter2],
where letter1 is the first (or only) letter in the range, and letter2
is the last letter in the range. DefSng can only be used at module level.
DefStr
Statement
DefStr letterrange[, letterrange]...
Specifies that all variables
and function return values that begin with the letters specified by the
letterrange arguments are automatically defined to be of the String
data type. The letterrange arguments should be constructed as letter1[-letter2],
where letter1 is the first (or only) letter in the range, and letter2
is the last letter in the range. DefStr can only be used at module level.
DefVar
Statement
DefVar letterrange[, letterrange]...
Specifies that all variables
and function return values that begin with the letters specified by the
letterrange arguments are automatically defined to be of the Variant
data type. The letterrange arguments should be constructed as letter1[-letter2],
where letter1 is the first (or only) letter in the range, and letter2
is the last letter in the range. DefVar can only be used at module level.
DeleteSetting
Statement
DeleteSetting appname, section[, key]
Deletes an application's section
or key setting entries from the System Registry. The appname argument
specifies the name of the application, and section is the name
of the section to be deleted. If the optional key argument is used,
then only that key (and not the whole section) will be deleted.
Dim
Statement
Dim [WithEvents] varname[([subscripts])] [As [New] type] [,[WithEvents]
varname[([subscripts])] [As [New] type]]...
Declares one or more variables
or objects. The varname argument is the name of the variable, and
the optional As [New] type indicates its data type. If the New
keyword is used, then an implicit creation of the object is made. The
optional WithEvents keyword (valid only when the Dim statement is used
in class modules) indicates that varname is an object variable
as is used to respond to events triggered by an ActiveX object. The optional
subscripts are the dimensions of an array variable.
Dir
Function
Dir[(pathname[, attributes])]
Returns a String value containing
the name of a file, directory, or folder that matches a pattern (specified
in the pathname argument) and/or a file attribute (specified in
attributes). The first time the Dir function is called, it returns
the name of a file based on the pathname and attributes
arguments. If the function is called again and no arguments are given,
then it returns the second file name for the given pathname and
attributes, and so on.
Do...Loop
Statement
Do [{While | Until} condition]
[statements]
[Exit Do]
[statements]
Loop
or
Do
[statements]
[Exit Do]
[statements]
Loop [{While | Until} condition]
Repeats one or more statements
while a condition is True or until a condition becomes True.
The optional Exit Do keywords pass control to the line of code immediately
following the Do...Loop structure.
DoEvents
Function
DoEvents( )
Temporarily gives control to
the operating system so that it can process other events. The DoEvents
function is typically used inside loops so that a program does not tie
up system resources for a long period of time.
End
Statement
End
End Function
End If
End Property
End Select
End Sub
End Type
End With
Ends a program (End), procedure
(End Function, End Property, or End Sub), type structure (End Type), or
program block (End If, End Select, or End With).
Enum
Statement
[Public | Private] Enum name
membername [= constantexpression]
membername [= constantexpression]
...
End Enum
Declares an enumeration type
named name that is composed of one or more members specified by
membername. Members can be assigned values using constantexpression.
The optional Public and Private keywords define the enumeration's scope.
Environ
Function
Environ({envstring | number})
Returns the String value of
the operating system variable specified by envstring or, alternatively,
the numeric order of the environment string in the environment-string
table specified by number.
EOF
Function
EOF(filenumber)
Returns a True or False value
(Integer) that indicates whether the end of file marker has been reached
for the Random or Input file associated with the filenumber
argument.
Erase
Statement
Erase arraylist
Reinitializes the elements
in one or more fixed-size array and frees up the dynamic-array storage
space that was taken up by the array(s). The arraylist argument
is one or more comma-delimited array names.
Error
Function
Error[(errornumber)]
Returns a String value that
contains the error message that corresponds to the errornumber
argument.
Error
Statement
Error errornumber
Causes an error to occur. The
errornumber argument indicates the type of error that should occur.
Event
Statement
[Public] Event procedurename [(arglist)]
Declares a user-defined event
with the name procedurename. The optional Public keyword indicates
that the Event should be visible throughout the project, even though that
is the default. The optional argument list (arglist) should contain
one or more arguments defined using the syntax:
[ByVal | ByRef] varname[()] [As type]
where varname is the
name of the argument, As type indicates the data type of the argument,
and the optional ByRef or ByVal keywords specify whether the argument
should be passed by reference (ByRef) or by value (ByVal). If ByRef
and ByVal are not specified, then the argument will be passed by reference.
Exit
Statement
Exit Do
Exit For
Exit Function
Exit Property
Exit Sub
Exits a procedure (Exit Function,
Exit Property, or Exit Sub) or looping structure (Exit Do or Exit For).
Exp
Function
Exp(number)
Returns a Double value that
is e (the base of natural logarithms) raised to the power specified
by number.
FileAttr
Function
FileAttr(filenumber, returntype)
Returns a Long value
that indicates the file mode for a file opened using the Open statement.
The argument filenumber is the file number for the open file, and
returntype indicates the type of information to be returned. Although
returntype can be set to 2 to return the operating system file
handle for the open file, it only works on 16-bit systems and should be
avoided in VB5. Instead, use a value of 1 for returntype to return
the open file type. The possible values returned by the FileAttr function
for indicating file type are: 1 for Input, 2 for Output, 4 for Random,
8 for Append, and 32 for Binary.
FileCopy
Statement
FileCopy source, destination
Copies the filename and path
specified by the source argument to the filename and path specified
by the destination argument.
FileDateTime
Function
FileDateTime(pathname)
Returns a Variant of subtype
Date that indicates the date and time when the file specified by the pathname
argument was last modified.
FileLen
Function
FileLen(pathname)
Returns a Long value that contains
the file size (in bytes) of the file specified by the pathname
argument.
Fix
Function
Fix(number)
Returns the integer portion
of the number specified by the number argument. If number
is negative, then Fix returns the first negative integer greater than
or equal to number.
For
Each...Next Statement
For Each element In group
[statements]
[Exit For]
[statements]
Next [element]
Executes one or more statements
for each element in the array or collection specified by group.
The optional Exit For can be used to immediately exit the looping structure.
For...Next
Statement
For counter = start To end [Step step]
[statements]
[Exit For]
[statements]
Next [counter]
Executes one or more statements
a specified number of times. The counter argument is a variable
used to increment from start to end. By default, counter
is incremented by 1 each time the loop is executed, although the optional
step argument can be used to specify a different increment. The
optional Exit For can be used to immediately exit the looping structure.
Format
Function
Format(expression[, format[, firstdayofweek[, _ firstweekofyear]]])
Returns a Variant of subtype
String that contains the value specified by expression using a
format defined by the format argument. The format argument
uses codes (for example, d for days or # for numbers) to
determine how expression will be formatted. The optional firstdayofweek
and firstweekofyear arguments are used when formatting certain
values.
FreeFile
Function
FreeFile[(rangenumber)]
Returns an Integer value the
represents the next file number available for use with the Open statement.
The optional rangenumber argument can be used to specify which
range of file numbers should be used: 0 (the default) for file numbers
in the range of 1-255, or 1 for file numbers in the range of 256-511.
Function
Statement
[Public | Private | Friend] [Static] Function name _ [(arglist)] [As type]
[statements]
[name = expression]
[Exit Function]
[statements]
[name = expression]
End Function
Declares the various parts
of a Function procedure. The optional Public, Private, and Friend keywords
can be used to define the Function's scope, and the optional Static keyword
indicates that the procedure's local variables are preserved between calls
to the Function. The name argument specifies the name of the Function
procedure and can be assigned a value (name = expression)
that will be returned by the procedure. The data type of the return value
can be specified using the As type clause. The optional Exit
Function can be used to exit the Function procedure immediately.
The optional list of arguments
(arglist) defines the arguments that will be passed to the procedure.
The arguments should use the following syntax:
[Optional] [ByVal | ByRef] [ParamArray] varname[()] [As _ type] [= default value]
where the Optional keyword
can be used to specify that the argument is not required (default value
assigns the argument's default value), ByVal and ByRef determine whether
the argument should be passed by value or by reference (the default),
and the ParamArray keyword specifies that the argument is an Optional
array of Variant elements. ParamArray can only be used with the last argument
in the argument list.
FV
Function
FV(rate, nper, pmt[, pv[, type]])
Returns a Double value
that indicates the future value of an annuity based on a number (nper)
of periodic fixed payment amounts (pmt) and a fixed interest rate
(rate). The optional pv argument specifies a present value
or lump sum of a series of future payments, and the optional type
argument specifies when payments are due (0 for end of the payment period,
the default; 1 for beginning of the payment period).
Get
Statement
Get [#]filenumber,[ recnumber,] varname
Reads data from the open disk
file corresponding to the filenumber argument into a variable (varname).
Get works with files open as Random or Binary, and a record number (recnumber)
can be specified when retrieving data from a Random file. When using Binary
files, recnumber can alternatively be used to specify the byte
position from which the data is to be read.
GetAllSettings
Function
GetAllSettings(appname, section)
Returns a list of key settings
and their values from a specific application (appname) entry and
section (section) in the System Registry.
GetAttr
Function
GetAttr(pathname)
Returns an Integer value that
represents the attributes for the file, directory, or folder specified
by the pathname argument. The value returned can be compared bitwise
with several VB constants (vbNormal, vbReadOnly, vbHidden, vbSystem, vbDirectory,
and vbArchive) to determine which attributes are set.
GetAutoServerSettings
Function
object.GetAutoServerSettings([progid], [clsid])
Returns a Variant array that
contains information concerning the state of an ActiveX object's
registration. The optional progid and clsid can be included
to specify the object's ProgID and CLSID, respectively. The values of
the elements of the Variant array that are returned by GetAutoServerSettings
are, in order: local/remote registration of object (True if the object
is registered remotely), the remote machine name, the RPC network protocol
name, and the RPC authentication level.
GetObject
Function
GetObject([pathname] [,class])
Returns a reference to an object
of type class. The pathname argument can be included to
specify the path and filename from which the object should be retrieved;
however, if it is omitted, then the class name must be specified.
GetSetting
Function
GetSetting(appname, section, key[, default])
Returns a single key setting
value from a specific application (appname) entry and section (section)
in the System Registry. If no value is set for the key setting specified,
then the optional default value can be returned. If default is
omitted, then the default value returned will be a zero-length string.
GoSub...Return
Statement
GoSub line
...
line
...
Return
Transfers program control to
the subroutine indicated by the line label or line number line
until the Return statement is reached; then returns control to the line
of code immediately following the GoSub statement.
GoTo
Statement
GoTo line
Transfers program control to
the line of code specified by the line label or line number line.
The line must be inside the procedure that contains the GoTo statement.
Hex
Function
Hex(number)
Returns a String value that
represents the hexadecimal value of the argument number.
Hour
Function
Hour(time)
Returns a Variant of subtype
Integer that represents the hour (0[nd]23) of the time value specified
by the time argument.
If...Then...Else
Statement
If condition Then [statements] [Else elsestatements]
or
If condition Then
[statements]
[ElseIf condition-n Then
[elseifstatements] ...
[Else
[elsestatements]]
End If
Conditionally executes one
or more statements if the value expressed by condition is
True. One or more ElseIf clauses can be included to test other conditions
and execute other statements (elseifstatements) if the preceding
condition is False. An Else clause can also be included to execute other
statements (elsestatements) if none of the preceding conditions
are True.
IIf
Function
IIf(expression, truepart, falsepart)
Returns one of two values based
on whether expression evaluates to True or False. If True, then
IIf returns the truepart value; if False, then the falsepart
value is returned.
IMEStatus
Function
IMEStatus
Returns an Integer value that
represents Windows' current Input Method Editor (IME) mode. IMEStatus
is only available in Far East versions.
Implements
Statement
Implements [interfacename | class]
Specifies an interface (interfacename)
or class (class) that will be implemented in the class module in
which the Implements statement is used.
Input
# Statement
Input #filenumber, varlist
Reads data from the open file
associated with the filenumber argument and places it in the variables
in the varlist argument. The varlist argument should contain
one or more comma-delimited variables.
Input
Function
Input(number, [#]filenumber)
Returns a String value containing
characters read in from the open file that corresponds to the filenumber
argument. The number of characters to be read in are specified by the
number argument.
InputBox
Function
InputBox(prompt[, title][, default][, xpos][, _ ypos][,helpfile, context])
Displays a dialog box and waits
for the user to enter text or click a button; then returns what the user
entered in a String value. The prompt argument specifies the message
to be displayed in the dialog box, title specifies an optional
caption for the dialog box's title bar, and default specifies the
optional default value returned by the InputBox function if no value is
entered by the user. The optional xpos and ypos arguments
specify (in twips) the horizontal and vertical position of the dialog
box on the screen. The optional helpfile and context arguments
are used to provide context-sensitive Help for the dialog box.
InStr
Function
InStr([start, ]string1, string2[, compare])
Returns a Variant of subtype
Long that specifies the starting position of the first occurrence of a
substring (string2) within another string (string1). The
optional start argument specifies from which character in string2
to start searching; the default is 1 (first character). The optional compare
argument specifies the type of string comparison that will be made (0
for binary or 1 for textual noncase-sensitive).
Int
Function
Int(number)
Returns the integer portion
of the number specified by the number argument. If number
is negative, then Int returns the first negative integer less than or
equal to number.
IPmt
Function
IPmt(rate, per, nper, pv[, fv[, type]])
Returns a Double value that
indicates the interest payment for a fixed-period annuity based on a number
(nper) of periodic fixed payments (per) and a fixed interest
rate (rate). The pv argument specifies the present value
of a series of payments or receipts. The optional fv argument specifies
the future value or cash balance left after the final payment. The optional
type argument specifies when payments are due (0 for end of the
payment period, the default; 1 for beginning of the payment period).
IRR
Function
IRR(values()[, guess])
Returns a Double value indicating
the internal rate of return for an array of values that represent
cash flow. The values() array must contain at least one negative
value (payment) and one positive value (receipt). The optional guess
argument specifies an estimate value to be returned by IRR (default estimate
is .1).
IsArray
Function
IsArray(varname)
Returns a Boolean value that
indicates whether the variable specified by varname is an array.
IsDate
Function
IsDate(expression)
Returns a Boolean value that
indicates whether expression is capable of being converted to a
date value.
IsEmpty
Function
IsEmpty(expression)
Returns a Boolean value that
indicates whether a numeric or string expression has been initialized.
IsError
Function
IsError(expression)
Returns a Boolean value that
indicates whether a given expression is an error value.
IsMissing
Function
IsMissing(argname)
Returns a Boolean value that
indicates whether an optional Variant argument (argname) has been
passed to a procedure. IsMissing returns True if no value has been provided
for the specified argument.
IsNull
Function
IsNull(expression)
Returns a Boolean value that
indicates whether a given expression contains no data and is Null.
IsNumeric
Function
IsNumeric(expression)
Returns a Boolean value that
indicates whether a given expression can be evaluated as a numeric
value.
IsObject
Function
IsObject(identifier)
Returns a Boolean value that
indicates whether a given identifier represents an object variable.
Kill
Statement
Kill pathname
Deletes the file(s) or directory
represented by the pathname argument. Filenames in the pathname
argument can contain wildcards, allowing multiple files to be deleted.
LBound
Function
LBound(arrayname[, dimension])
Returns a Long value that represents
the smallest subscript for a dimensioned array (arrayname). For
multidimensional arrays, the dimension argument can be included
to specify which dimension should be used.
LCase
Function
LCase(string)
Converts a string to
all lowercase characters and returns a new String value.
Left
Function
Left(string, length)
Returns a String value length
characters long that is taken from the left side of a given string.
Len
Function
Len(string | varname)
Returns a Long value that indicates
the number of characters in a string or, alternatively, the number
of bytes required to store a particular variable (varname).
Let
Statement
[Let] varname = expression
Assigns the value of an expression
to a variable (varname). The Let keyword is usually omitted and
is assumed by Visual Basic.
Line
Input # Statement
Line Input #filenumber, varname
Reads a line of data (ending
with a carriage return or carriage return-linefeed) from an open disk
file corresponding to the filenumber argument. The data is placed
in the String or Variant variable specified by varname.
Load
Statement
Load object
Loads an object, such
as a form or control, into memory.
LoadPicture
Function
LoadPicture([stringexpression])
Loads the image specified by
the stringexpression argument and returns it. This allows pictures
to be loaded in and assigned to a Form's Picture property, a PictureBox
control, or an Image control. If no stringexpression argument is
given, then LoadPicture returns an empty picture.
LoadResData
Function
LoadResData(index, format)
Loads data from the resource
(.RES) file with the identifier of the index argument. The format
argument specifies the format of the data (1 for cursors, 2 for bitmaps,
3 for icons, 4 for menus, 5 for dialog boxes, 6 for strings, 7 for font
directories, 8 for fonts, 9 for accelerator tables, 10 for user-defined
resources, 12 for group cursors, and 14 for group icons). The data returned
by the LoadResData function can be assigned to a variable or object of
the appropriate type.
LoadResPicture
Function
LoadResPicture(index, format)
Loads a bitmap, icon, or cursor
from the resource (.RES) file with the identifier of the index
argument. The format argument specifies the format of the data
(0 for bitmaps, 1 for icons, and 2 for cursors). The data returned by
the LoadResPicture function can be assigned to an object of the appropriate
type.
LoadResString
Function
LoadResString(index)
Loads a string from the resource
(.RES) file with the identifier of the index argument. The string
that is returned can be assigned to a variable of String or Variant data
type.
Loc
Function
Loc(filenumber)
Returns a Long value that indicates
the current byte position within the open file that corresponds to the
filenumber argument.
Lock
Statement
Lock [#]filenumber[, recordrange]
Prevents another process from
accessing all or part of the open file that corresponds to the filenumber
argument. The recordrange argument refers to a range of records
(or bytes) that are to be locked and should use the syntax:
recnumber | [start] To end
where recnumber is the
record number (for Random files) or byte position (for Binary files) where
locking should begin. Alternatively, the starting and ending record numbers
or bytes to be locked can be specified using the start and end
arguments.
LOF
Function
LOF(filenumber)
Returns a Boolean value that
represents the byte size of the open file that corresponds to the filenumber
argument.
Log
Function
Log(number)
Returns a Double value that
represents the natural logarithm of a specified number.
LSet
Statement
LSet stringvar = string
or
LSet varname1 = varname2
In the first syntax, LSet assigns
a string value to a String variable (stringvar), left-aligning
the string to the String variable. In the second syntax, LSet copies a
variable (varname2) from one user-defined type to a variable (varname1)
in another user-defined type.
LTrim
Function
LTrim(string)
Returns a Variant of subtype
String that contains a copy of a given string with any leading
spaces removed.
Mid
Function
Mid(string, start[, length])
Returns a String value of one
or more characters, taken from the String variable specified by the string
argument. The start argument specifies the character position within
string where the new String is to be obtained, and the optional
length argument specifies how many characters are to be taken from
string. If no length is specified, then all the characters
in string (starting at the position given in the start argument)
are used.
Mid
Statement
Mid(stringvar, start[, length]) = string
Replaces one or more characters
in a String variable (stringvar) with another string. The
start argument specifies the character position within stringvar
to place the new string, and the optional length argument
specifies how many characters of string should be used. If length
is omitted, then the entire string is used.
Minute
Function
Minute(time)
Returns a Variant of subtype
Integer that represents the minute (0-59) of the time value specified
by the time argument.
MIRR
Function
MIRR(values(), financerate, reinvestrate)
Returns a Double value that
represents the modified internal rate of return for an array of values
that represent cash flow. The values() array must contain at least
one negative value (payment) and one positive value (receipt). The financerate
argument specifies the interest rate paid as a cost of financing, and
the reinvestrate argument specifies the interest rate received
on gains from cash reinvestment.
MkDir
Statement
MkDir path
Creates the new directory or
folder specified by the path argument.
Month
Function
Month(date)
Returns a Variant of subtype
Integer that represents the month (1[nd]12) for the date value specified
by the date argument.
MsgBox
Function
MsgBox(prompt[, buttons][, title][, helpfile, context]
Displays a message in a dialog
box with one or more buttons and waits for the user to respond. MsgBox
then returns an Integer value that represents the button that was clicked.
The prompt argument specifies the message to be displayed in the
dialog box, and title specifies an optional caption for the dialog
box's title bar. The optional buttons argument specifies which
buttons will be displayed. The optional helpfile and context
arguments are used to provide context-sensitive Help for the dialog box.
Name
Statement
Name oldpathname As newpathname
Renames the file, directory,
or folder specified by the oldpathname argument to the name specified
by newpathname.
Now
Function
Now
Returns a Variant of subtype
Date that contains the current system date and time.
NPer
Function
NPer(rate, pmt, pv[, fv[, type]])
Returns a Double value that
indicates the number of periods for an annuity based on periodic fixed
payments (pmt) and a fixed interest rate (rate). The pv
argument specifies the present value of a series of payments or receipts.
The optional fv argument specifies the future value or cash balance
left after the final payment. The optional type argument specifies
when payments are due (0 for end of the payment period, the default; 1
for beginning of the payment period).
NPV
Function
NPV(rate, values())
Returns a Double value that
represents the present value of an investment based on a discount rate
(rate) and an array of values that represent cash flow.
The values() array must contain at least one negative value (payment)
and one positive value (receipt).
Oct
Function
Oct(number)
Returns a String value that
represents the octal value of the argument number.
On
Error Statement
On Error GoTo line
On Error Resume Next
On Error GoTo 0
Enables or disables the use
of an error-handling routine. The On Error statement can specify a line
label or line number (specified by the line argument) to branch
to when an error occurs, allowing error-handling to be enabled. Alternatively,
using On Error Resume Next causes program control to be transferred to
the line of code immediately following the line of code that causes an
error. Finally, On Error GoTo 0 disables all error-handling.
On...GoSub
Statement
On expression GoSub destinationlist
Evaluates a given expression
and, depending on its value, transfers program control to a certain subroutine.
The possible subroutines are contained in the destinationlist argument,
which contains one or more comma-delimited line labels or line numbers.
If expression evaluates to 1, then the first subroutine in the
destinationlist is used; if it evaluates to 2, then the second
subroutine in the destinationlist is used; and so on. Control is
transferred to the line of code immediately following the On...GoSub line
when a Return statement is encountered.
On...GoTo
Statement
On expression GoTo destinationlist
Evaluates a given expression
and, depending on its value, transfers program control to a certain line
label or line number. The possible transfer points are contained in the
destinationlist argument, which contains one or more comma-delimited
line labels or line numbers. If expression evaluates to 1, then
the first line label in the destinationlist is used; if it evaluates
to 2, then the second line label in the destinationlist is used;
and so on.
Open
Statement
Open pathname For mode [Access access] [lock] As _ [#]filenumber [Len=reclength]
Opens a file for input/output
and assigns it to the given filenumber. The pathname argument
specifies the name of the file to open, and mode indicates the
file mode (Append, Binary, Input, Output, or Random). The optional Access
clause can be used to specify permissions for the file (Read, Write, or
Read Write). The optional lock argument can specify the operations
that can be performed on the file by other processes (Shared, Lock Read,
Lock Write, or Lock Read Write). The reclength argument can be
used to specify the record size for random files or the buffer size for
sequential files.
Option
Base Statement
Option Base [0 | 1]
Declares the default lower
bound of array subscripts. Option Base can only be used at module level.
Option
Compare Statement
Option Compare [Binary | Text | Database]
Declares the default method
used for string comparisons. Option Compare can only be used at module
level.
Option
Explicit Statement
Option Explicit
Forces explicit declaration
of all variables in a module. If Option Explicit is not used, undeclared
variables are automatically typed as Variants. Option Explicit can only
be used at module level.
Option
Private Statement
Option Private Module
Prevents a module's contents
(that is, variables and objects) from being used outside its project.
Option Private is only necessary when working with host applications that
allow variables and objects to be referenced across multiple projects.
Partition
Function
Partition(number, start, stop, interval)
Returns a Variant of subtype
String that describes a range of numbers 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.
Pmt
Function
Pmt(rate, nper, pv[, fv[, type]])
Returns a Double value that
indicates the payment for an annuity based on a number (nper) of
periodic fixed payments and a fixed interest rate (rate). The pv
argument specifies the present value of a series of payments or | 
