The OPTION BASE statement is used to set the default lower bound of arrays.
OPTION BASE 0|1
- This statement affects array declarations where the lower bound of a dimension is not specified. See DIM, REDIM, STATIC, COMMON.
- By default, the lower bound for arrays is zero, and may be changed to one.
- OPTION BASE must be used before any array declarations, if at all.
- Otherwise, arrays will be dimensioned from element 0 if you DIM just the upper bounds.
- Statement should be set before any arrays are dimensioned (DIM).
' Set the default lower bound for array declarations to one. OPTION BASE 1 ' Declare a 5-element one-dimensional array with element indexes of one through five. DIM array(5) AS INTEGER PRINT LBOUND(array)
' Set the default lower bound for array declarations to zero. This statement has no real effect, ' but it may be useful to emphasize the default behavior in order to eliminate any chance of confusion. OPTION BASE 0 ' Declare an 18-element two-dimensional array with element indexes of zero through two for the first dimension, ' and 10 through 15 for the second dimension. DIM array(2, 10 to 15) AS INTEGER PRINT LBOUND(array, 1) PRINT LBOUND(array, 2)
Alternative: DIM arrays using upper and lower bounds as shown:
- DIM Array(1 TO 200)