Name

Dim Statement

Syntax

Dim varname[([subscripts])], varname[([subscripts])]
varname

Use: Required

Your chosen name for the variable.

subscripts

Use: Optional

Dimensions of an array variable.

Description

Declares and allocates storage space in memory for variables. The Dim statement is used either at the start of a procedure or the start of a global script block. In the first case, the variable declared using Dim is local to the procedure. In the second, it’s available throughout the module.

Rules at a Glance

  • You can declare multiple variables in a single Dim statement, as long as you use a comma to delimit them.

  • When variables are first initialized with the Dim statement, they have a value of Empty. In addition, if a variable has been initialized but not assigned a value, the following expressions will both evaluate to True:

    If vVar = 0 Then     
    If vVar = "" Then
  • To declare array variables, use the following syntax:

    Fixed length, single dimension

    Dim arrayname ( upper )

    Example: Dim myArray(10)

    Fixed length, multidimensional

    Dim arrayname ( upper , upper , ...)

    Example: Dim MyArray(20,30)

    Variable length, single or multidimensional

    Dim arrayname ( )

    Example: Dim myArray( )

  • You can declare a multidimensional array with up to 60 dimensions.

  • Variable-length arrays can be resized using the ReDim statement. Fixed-length arrays can’t be resized.

Example

The example shows how to use the Dim statement to define a variable that receives an array returned by a function:

Dim Input, NumArray Input = InputBox("Enter three ...

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