Name
LBound Function
Class
Microsoft.VisualBasic.Information
Syntax
LBound(array[, rank]
)
-
array
Use: Required
Data Type: Any array
An array whose lower bound is to be determined
-
rank
Use: Optional
Data Type: Integer
The dimension whose lower bound is desired
Return Value
An Integer whose value is 0
Description
Determines the lower boundary of a specified dimension of an array. The lower boundary is the smallest subscript you can access within the specified array.
Rules at a Glance
Unless it is passed an invalid argument, the
LBound
function always returns 0.If
array
is uninitialized, it generates an ArgumentNullException error when passed to theLBound
function. You can prevent this by comparingarray
toNothing
, as in the following code fragment:If Not oArray Is Nothing Then
To determine the lower limit of the first dimension of an array, set
rank
to 1, set it to 2 for the second, and so on.If
rank
isn’t specified, 1 is assumed.
Programming Tips and Gotchas
Since VB .NET does not allow you to change the lower bound of an
array, the LBound
function would appear to be
superfluous except for reasons of backward compatibility. Its
continued use may be a good idea, though, in the event that a future
version of VB .NET allows you to set the lower boundary of an array.
VB .NET/VB 6 Differences
Since VB 6 offers a number of ways to set the lower bound of all
arrays or a specific array, the LBound
function is particularly useful when iterating the elements of an array. In VB .NET, its use is a matter ...
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