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  ◄Declaring Simple Variables►   ◄AS Declarations►   ◄Contents►   ◄Index►
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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, REDIM (for arrays), SHARED,
or STATIC, and the "type" can be either INTEGER, LONG, SINGLE, DOUBLE,
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:
 
  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
        .
        .
        .