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AS Declaration Statements
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AS Declaration Statements
■ In general, AS clause syntax is:
declare variablename AS type
where declare can be DIM, COMMON, FUNCTION, SHARED, or STATIC, and type
can be any valid data type (default is SINGLE). For example, the following
statement declares the variable A as having a long-integer type:
DIM A AS LONG
■ If you declare a variable with an AS clause, every declaration of the
variable must use the AS clause. For example, in the following code, AS
is required in the COMMON statement because AS is used in the DIM
statement:
CONST MAXEMPLOYEES = 250
DIM EmpNames(MAXEMPLOYEES) AS STRING
COMMON EmpNames() AS STRING
.
.
.
See: ◄COMMON Statement► ◄DIM Statement►
■ String variables declared in an AS STRING clause can be either:
• Variable-length (depends on the length of the string assigned)
• Fixed-length (length is specified by adding "* number" to the AS STRING
clause, where number is the length of the string in bytes)
For example:
DIM String1 AS STRING 'String1 can have a variable length
DIM String2 AS STRING*7 'String2 has a fixed length of 7 bytes
String1 = "1234567890"
String2 = "1234567890"
PRINT String1
PRINT String2
produces this output:
1234567890
1234567
■ User-defined (or record) variables can be declared by specifying the name
of the record variable in the AS clause of a declaration:
TYPE InventoryItem 'Declare group as single type
Description AS STRING * 25 'Declare fixed-length string
Number AS STRING * 10 'Declare fixed-length string
Quantity AS LONG 'Declare long (4-byte) integer
OrderPoint AS LONG 'Declare long (4-byte) integer
END TYPE
.
.
.
DIM CurrentItem AS InventoryItem, PreviousItem AS InventoryItem
See: ◄TYPE Statement►
■ To refer to individual elements of the new variable, use the dot (.)
notation form:
variablename.elementname
For example:
IF CurrentItem.Description = "Ergonomic Desk Chair" THEN
PRINT CurrentItem.Number; CurrentItem.Quantity
END IF
See: ◄Variables Summary►