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AS Declaration Statements
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AS Declaration Statements
Declare the variable in a declaration having the form
declare variablename AS type
where the "declare" can be either DIM, COMMON, SHARED, or STATIC,
and the "type" can be either INTEGER, LONG, SINGLE, DOUBLE, CURRENCY,
STRING, or a user-defined type. For example, the following statement
declares the variable A as having a long-integer type:
DIM A AS LONG
String variables declared in an AS STRING clause can be either variable-
length strings or fixed-length strings. Variable-length strings are
expandable: their length depends on the length of any string assigned to
them. Fixed-length strings have a constant length, specified by adding
"*number" to the AS STRING clause, where number is the length of the
string in bytes. For example:
' String1 can have a variable length:
DIM String1 AS STRING
' String2 has a fixed length of 7 bytes.
DIM String2 AS STRING*7
String1 = "1234567890"
String2 = "1234567890"
PRINT String1
PRINT String2
Output:
1234567890
1234567
Declare record variables by using the name of the user type in the
AS clause of the declaration:
TYPE InventoryItem
Description AS STRING * 25
Number AS STRING * 10
Quantity AS LONG
OrderPoint AS LONG
END TYPE
...
DIM CurrentItem AS InventoryItem, PreviousItem AS InventoryItem
To refer to individual elements of the new variable, use the format
variablename.elementname
as in the following example:
IF CurrentItem.Description = "Ergonomic Desk Chair" THEN
PRINT CurrentItem.Number; CurrentItem.Quantity
END IF
Note: If you declare a variable with an AS clause, every declaration of the
variable must use the AS clause. For example, in the following
fragment the AS clause is required in the COMMON statement because AS
was used in the DIM statement:
CONST MAXEMPLOYEES = 250
DIM EmpNames(MAXEMPLOYEES) AS STRING
COMMON EmpNames() AS STRING
.
.
.