Syntax

Public name [(subscripts)] [As type] [,name [(subscripts)] [As type]]...

Description

Declares a list of public variables and their corresponding types and sizes.

Comments

Public variables are global to all Subs and Functions in all scripts.

If a type-declaration character is used when specifying name (such as %, @, &, $, or !), the optional [As type] expression is not allowed. For example, the following are allowed:

  Public foo As Integer
  Public foo%

The subscripts parameter allows the declaration of arrays. This parameter uses the following syntax:

  [lower To] upper [,[lower To] upper]...

The lower and upper parameters are integers specifying the lower and upper bounds of the array. If lower is not specified, then the lower bound as specified by Option Base is used (or 1 if no Option Base statement has been encountered). Up to 60 array dimensions are allowed.

The total size of an array (not counting space for strings) is limited to 64K.

Dynamic arrays are declared by not specifying any bounds:

  Public a()

The type parameter specifies the type of the data item being declared. It can be any of the following data types: String, Integer, Long, Single, Double, Currency, Object, data object, built-in data type, or any user-defined data type.

If a variable is seen that has not been explicitly declared with either Dim, Public, or Private, then it will be implicitly declared local to the routine in which it is used.

For compatibility, the keyword Global is also supported. It has the same meaning as Public.

Fixed-Length Strings

Fixed-length strings are declared by adding a length to the String type-declaration character:

  Public name As String * length

where length is a literal number specifying the string's length.

Initial Values

All declared variables are given initial values, as described in the following table:

Parameter

Description

Integer

0

Long

0

Double

0.0

Single

0.0

Currency

0.0

Date

December 31, 1899 00:00:00

Object

Nothing

Boolean

False

Variant

Empty

String

"" (zero-length string)

User-defined type

Each element of the structure is given a default value, as described above.

Arrays

Each element of the array is given a default value, as described above.

Sharing Variables

When sharing variables, you must ensure that the declarations of the shared variables are the same in each script that uses those variables. If the public variable being shared is a user-defined structure, then the structure definitions must be exactly the same.

Example

This example uses a subroutine to calculate the area of ten circles and displays the result in a dialog box. The variables R and Ar are declared as Public variables so that they can be used in both Main and Area.

Const crlf = Chr$(13) + Chr$(10)

Public x#,ar#

Sub Area()
  ar# = (x# ^ 2) * Pi
End Sub

Sub Main()
  msg1 = "The area of the ten circles are:" & crlf & crlf
  For x# = 1 To 10
    Area
    msg1 = msg1 & x# & ": " & Format(ar#,"fixed") & Basic.Eoln$
  Next x#
  MsgBox msg1
End Sub

See Also

Dim (statement); Redim (statement); Public (statement); Option Base (statement).

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