UNIDAD 1: VBSCRIPT ELEMENTOS BASICOS

TEMA APENDIC1D: VISUAL BASIC SCRIPT PALABRAS RESERVADAS


Category/Keyword

Type

Usage

Arithmetic

Atn

Function

Returns the arctangent of a number Atn(number)

Cos

Function

Returns the cosine of an angle Cos(number)

Exp

Function

Returns a number raised to a power Exp(number)

Log

Function

Returns the logarithm of a number Log(number)

Randomize

Statement

Primes the internal random number generator Randomize

Rnd

Function

Returns a random number Rnd

Sin

Function

Returns the sine of an angle Sin(number)

Sqr

Function

Returns the square root of a number Sqr(number)

Tan

Function

Returns the tangent of an angle Tan(number)

Array handling

Dim

Statement

Declares an array Dim arrayname([subscripts])

Erase

Statement

Clears the contents of an array Erase arrayname

IsArray

Function

Returns True if var is an array, and False if not IsArray(var)

Lbound

Function

In VBScript, always returns 0 Lbound(arrayname)

Preserve

Statement

Copies the contents of a dynamic array to a resized dynamic array Redim Preserve arrayname(subscripts)

ReDim

Statement

Declares a dynamic array or redimensions a dynamic array (see Preserve) ReDim arrayname() or ReDim arrayname([subscripts])

UBound

Statement

Returns the largest subscript of an array Ubound(arrayname)

Assignment

=

Operator

Assigns a value to a variable or property variable = value

Set

Statement

Assigns an object reference to a variable Set variable = object

Comment

Rem

Statement

Declares the following line as a comment to be ignored by the language engine Rem comment_text

Constants/Literals

Empty

Literal

Declares a special uninitialized variable value variable = Empty

False

Constant

A Boolean value representing 0 variable = False

Nothing

Literal

Used to disassociate an object reference from a variable; used in conjunction with Set Set variable = Nothing

Null

Literal

Represents no valid data variable = Null

True

Constant

Boolean value representing -1 variable = True

Conversions

Abs

Function

Returns the unsigned (absolute) value of a number Abs(number)

Asc

Function

Returns the ANSI/ASCII code of a character Asc(string)

CBool

Function

Returns a Boolean subtype Variant value from any valid expression CBool(expression)

CByte

Function

Returns a Byte subtype Variant value from any valid expression Cbyte(expression)

CDate

Function

Returns a Date subtype Variant value from any valid date expression CDate(expression)

CDbl

Function

Returns a Double Precision subtype Variant value from any valid numeric expression CDbl(expression)

Chr

Function

Returns the character corresponding to the ANSI or ASCII code Chr(number)

CInt

Function

Returns an Integer subtype Variant value from any valid numeric expression CInt(expression)

CLng

Function

Returns a Long Integer subtype Variant value from any valid numeric expression CLng(expression)

CSng

Function

Returns a Single Precision subtype Variant value from any valid numeric expression CSng(expression)

CStr

Function

Returns a String subtype Variant value from any valid expression CStr(expression)

DateSerial

Function

Returns a Date subtype Variant from valid year, month, and day values DateSerial(year,month,day)

DateValue

Function

Returns a Date subtype Variant value from any valid date expression DateValue(expression)

Hex

Function

Returns a String subtype Variant representing the hexadecimal value of a number Hex(number)

Int

Function

Returns an Integer subtype Variant rounded down from the number supplied Int(number)

Fix

Function

Returns an Integer subtype Variant rounded up from the number supplied Fix(number)

Oct

Function

Returns a String subtype Variant representing the octal value of a number Hex(number)

Sgn

Function

Returns an Integer subtype Variant representing the sign of a number Sgn(number) values > 0 return 1 values = 0 return 0 values < 0 return -1

TimeSerial

Function

Returns a Date subtype Variant from valid hour, minute, and second values TimeSerial(hour,minute,second)

TimeValue

Function

Returns a Date subtype Variant value from any valid time expression TimeValue(expression)

Dates and Times

Date

Function

Returns the current system date Date()

DateSerial

Function

Returns a Date subtype Variant from valid year, month, and day values. DateSerial(year,month,day)

DateValue

Function

Returns a Date subtype Variant value from any valid date expression. DateValue(expression)

Day

Function

Returns an Integer subtype Variant representing the day (1-31) from a valid date expression Day(dateexpression)

Hour

Function

Returns an Integer subtype Variant representing the hour (0-23) from a valid time expression Hour(timeexpression)

Minute

Function

Returns an Integer subtype Variant representing the minute (0-60) from a valid time expression Minute(timeexpression)

Month

Function

Returns an Integer subtype Variant representing the month (1-12) from a valid date expression Month(dateexpression)

Now

Function

Returns the current date and time of the system Now()

Second

Function

Returns an Integer subtype Variant representing the second (0-60) from a valid time expression Second(timeexpression)

Time

Function

Returns the current system time Time()

TimeSerial

Function

Returns a Date subtype Variant from valid hour, minute and second values TimeSerial(hour,minute,second)

TimeValue

Function

Returns a Date subtype Variant value from any valid time expression TimeValue(expression)

Weekday

Function

Returns an Integer subtype Variant between 1 and 7 representing the day of the week, starting at Sunday, from a date expression Weekday(dateexpression)

Year

Function

Returns an Integer subtype Variant representing the year from a valid date expression Year(dateexpression)

Declarations

Dim

Statement

Declares a variable Dim variable

End

Statement

Declares the end of a Sub procedure or function End Sub End Function

Exit

Statement

Use with Do, For, Function, or Sub to prematurely exit the routine Exit Do/For/Function/Sub

Function

Statement

Declares a function and the argument list passed into the function, and declares the end of a function; also used with Exit to prematurely end a function Function functionname(argumentlist) Exit Function End Function Public variable

Sub

Statement

Declares a custom procedure or event handler and the argument list, if any, and declares the end of a custom procedure or event handler; also used with Exit to prematurely end a custom procedure or event handler Sub subroutinename([argumentlist]) Exit Sub End Sub

Error Handling

Clear

Method

A method of the Err object to reset the Err.Number property to 0 Err.Clear

Description

Property

A property of the Err object that contains a description of the last error as specified in the Err.Number property Err.Description

Err

Object

An object containing information about the last error Err.property|method

On Error

Statement

Used in conjunction with Resume Next to continue execution with the line directly following the line in which the error occurred On Error Resume Next

Raise

Method

A method of the Err object used to simulate the occurrence of an error specified by number Err.Raise(errornumber)

Number

Property

A property of the Err object that contains the error code for the last error, or 0 if no error has occurred Err.Number

Source

Property

Returns the name of the object or application that raised the error Err.Source

Input/Output

InputBox

Function

Displays a dialog box to allow user input InputBox(caption[,title][,value][,x][,y])

MsgBox

Function

Displays a dialog box MsgBox(prompt[, definition][, title])

Operators

+

Operator

Addition of two numerical expressions result = expr1 + expr2

And

Operator

Logical conjunction operator If expression AND expression Then

/

Operator

Division operator result = expression / expression

=

Operator

Equality operator If expression = expression Then

Eqv

Operator

Logical equivalence operator If expression Eqv expression Then

Operator

Exponentiation operator result = expression ^ expression

Operator

Greater than comparison If expression > expression Then

=

Operator

Greater than or equal to comparison If expression >= expression Then

Imp

Operator

Logical implication If expression Imp expression Then

<>

Operator

Inequality comparison If expression <> expression Then

\

Operator

Integer division operator result = expression \ expression

<

Operator

Less than comparison If expression < expression Then

Operator

Less than or equal to comparison If expression ⇐ expression Then

Mod

Operator

Modulus arithmetic; returns only the remainder of a division of two numbers result = expression mod expression

*

Operator

Multiplication result = expression * expression

-

Operator

Subtraction result = expression - expression

Or

Operator

Logical disjunction If expression Or expression Then

&

Operator

Concatenation of two string values result = string & string

Xor

Operator

Logical exclusion If expression Xor expression Then

Options

Option

Statement

Forces a compile-time error if an Explicit undeclared variable is found Option Explicit

Program Flow

Call

Statement

Passes execution to a subroutine or event handler; also can be used to replicate the actions of the user Call myroutine() Call cmdbutton_OnClick()

Do…Loop

Statement

Repeats code while a condition is met or until a condition is met Do While condition … Loop or Do Until condition … Loop

or Do … Loop While condition or Do … Loop Until condition

For…Next

Statement

Repeats a block of code until the counter reaches a given number For counter = lower to upper [step] … Next

If…Then…Else

Statement

Conditional execution of code If condition Then … (if condition met Else) … (if condition not met) End If

Select Case

Statement

Selective execution of code, where

testexpression must match expression Select Case testexpression Case expression … Case expression … Case Else End Select

While…Wend

Statement

Execution of a code block while a condition is met While expression … Wend

Strings

InStr

Function

Returns the starting point of one string within another string, or 0 if not found result = InStr(start,searched,sought)

Lcase

Function

Converts a string to lowercase result = LCase(string)

Left

Function

Returns the n leftmost characters of a string result = LCase(string)

Len

Function

Returns the length of a string result = Len(string)

Ltrim

Function

Removes all leading spaces result = LTrim(string)

Mid

Function

Returns a string of length L, starting at S within string result = Mid(string, S, L)

Right

Function

Returns the rightmost n characters result = Right(string, n)

RTrim

Function

Removes all trailing spaces from a string result = RTrim(string)

Space

Function

Returns a string consisting of n spaces result = Space(n)

StrComp

Function

Returns an Integer subtype Variant representing the result of a comparison of two strings result = StrComp(string1, string2) string1 < string2 returns -1 string1 < string2 returns 0 string1 < string2 returns 1

String

Function

Returns a string consisting of character C, of length L result = String(L, C)

Trim

Function

Removes both leading and trailing spaces result = Trim(string)

UCase

Function

Returns a string as uppercase alphabetical characters result = UCase(string)

Variants

IsArray

Function

Returns True (-1) if expression is an array, and False (0) if not result = IsArray(expression)

IsDate

Function

Returns True (-1) if expression is a valid date and False (0) if not result = IsDate(expression)

IsEmpty

Function

Returns True (-1) if expression equates to an Empty subtype and False (0) if not result = IsEmpty(expression)

IsNull

Function

Returns True (-1) if expression equates to a Null subtype and False (0) if not result = IsNull(expression)

IsNumeric

Function

Returns True (-1) if expression is a valid numeric expression and False (0) if not result = IsNumeric(expression)

VarType

Function

Returns an integer representing the sub data type of a Variant result = VarType(expression)

Politica de Privacidad