Common
Variable declaration and scope modifier
Declares a variable which is shared between code modules. A matching Common statement must appear in all other code modules using the variable.
The Shared optional parameter makes the variable global so that it can be used inside Subs and Functions, as well as at module level. Common arrays are always variable-length, and must be defined with an empty parameter list (), and its dimensions set in a later Dim or ReDim statement.
Output:
Syntax
Description
Declares a variable which is shared between code modules. A matching Common statement must appear in all other code modules using the variable.
The Shared optional parameter makes the variable global so that it can be used inside Subs and Functions, as well as at module level. Common arrays are always variable-length, and must be defined with an empty parameter list (), and its dimensions set in a later Dim or ReDim statement.
Example
'' common1.bas
Declare Sub initme()
Common Shared foo() As Double
ReDim foo(0 To 2) As Double
initme()
Print foo(0), foo(1), foo(2)
Declare Sub initme()
Common Shared foo() As Double
ReDim foo(0 To 2) As Double
initme()
Print foo(0), foo(1), foo(2)
'' common2.bas
Common Shared foo() As Double
Sub initme()
foo(0) = 4*Atn(1)
foo(1) = foo(0)/3
foo(2) = foo(1)*2
End Sub
Common Shared foo() As Double
Sub initme()
foo(0) = 4*Atn(1)
foo(1) = foo(0)/3
foo(2) = foo(1)*2
End Sub
Output:
3.141592653589793 1.047197551196598 2.094395102393195
Differences from QB
- The arrays will be always variable-length.
- blockname is not needed and must be removed because the order of declaration no longer matters, only the symbol names.
See also
