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62 lines
1.4 KiB
Markdown
62 lines
1.4 KiB
Markdown
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The [OPTION BASE](OPTION-BASE) statement is used to set the default lower bound of arrays.
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## Syntax
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> [OPTION BASE](OPTION-BASE) {0|1}
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## Description
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* This statement affects array declarations where the lower bound of a dimension is not specified.
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* When used, [OPTION BASE](OPTION-BASE) must come before any array declarations ([DIM](DIM)) to be affected.
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* By default, the lower bound for arrays is zero, and may be changed to one using the statement.
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* Otherwise, arrays will be dimensioned from element 0 if you DIM just the upper bounds.
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* You can also set other array boundaries by using [TO](TO) in the DIM declaration such as `DIM array(5 TO 10)`
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## Example(s)
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Set the default lower bound for array declarations to one.
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```vb
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OPTION BASE 1
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' Declare a 5-element one-dimensional array with element indexes of one through five.
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DIM array(5) AS INTEGER
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PRINT LBOUND(array)
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```
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```text
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1
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```
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Set the default lower bound for array declarations to zero.
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```vb
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OPTION BASE 0
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' Declare an 18-element two-dimensional array with element indexes of zero through two
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' for the first dimension, and 10 through 15 for the second dimension.
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DIM array(2, 10 to 15) AS INTEGER
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PRINT LBOUND(array, 1)
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PRINT LBOUND(array, 2)
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```
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```text
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0
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10
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```
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## See Also
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* [Arrays](Arrays), [LBOUND](LBOUND), [UBOUND](UBOUND)
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* [DIM](DIM), [REDIM](REDIM), [STATIC](STATIC), [COMMON](COMMON)
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