Difference between revisions of "OPTION BASE"

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{{PageDescription}}
 
{{PageDescription}}
 
* This statement affects array declarations where the lower bound of a dimension is not specified.
 
* This statement affects array declarations where the lower bound of a dimension is not specified.
* When used {{KW|OPTION BASE}} must be used before any array declarations ({{KW|DIM}}).
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* When used, {{KW|OPTION BASE}} must be used before any array declarations ({{KW|DIM}}).
 
* By default, the lower bound for arrays is zero, and may be changed to one using the statement.
 
* By default, the lower bound for arrays is zero, and may be changed to one using the statement.
 
* Otherwise, arrays will be dimensioned from element 0 if you DIM just the upper bounds.
 
* Otherwise, arrays will be dimensioned from element 0 if you DIM just the upper bounds.
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{{PageExamples}}
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''Example 1:'' Set the default lower bound for array declarations to one.
{{CodeStart}}' Set the default lower bound for array declarations to one.
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{{CodeStart}}
 
{{Cl|OPTION BASE}} 1
 
{{Cl|OPTION BASE}} 1
  
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{{CodeStart}}' Set the default lower bound for array declarations to zero. This statement has no
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''Example 2:'' Set the default lower bound for array declarations to zero.
' real effect, but it may be useful to emphasize the default behavior in order to
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{{CodeStart}} '' ''
' eliminate any chance of confusion.
 
 
{{Cl|OPTION BASE}} 0
 
{{Cl|OPTION BASE}} 0
  
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  10
 
  10
 
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Revision as of 05:41, 17 March 2011

The OPTION BASE statement is used to set the default lower bound of arrays.


Syntax

OPTION BASE {0|1}


Description

  • This statement affects array declarations where the lower bound of a dimension is not specified.
  • When used, OPTION BASE must be used before any array declarations (DIM).
  • By default, the lower bound for arrays is zero, and may be changed to one using the statement.
  • Otherwise, arrays will be dimensioned from element 0 if you DIM just the upper bounds.
  • You can also set other array boundaries by using TO in the DIM such as: DIM array(5 TO 10)


Example 1: 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)

1


Example 2: Set the default lower bound for array declarations to zero.

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)

0 10


See also



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