Basic 7.00 Can Assign an Array to an Array If in a TYPE (58733)






This article was previously published under Q58733

SUMMARY

Some languages, such as Pascal, allow you to assign one array directly to another, which copies all the elements from one array to another. Microsoft Basic cannot do this, except in Microsoft Basic Professional Development System (PDS) versions 7.00 and 7.10 where you can now directly assign one static array to another by defining the array in a user-defined-TYPE variable and then assigning one variable of this TYPE to another.

Using a variable of a TYPE that contains an array, you can also write an entire array to a file using a single PUT# statement.

MORE INFORMATION

Note that in Microsoft QuickBasic versions 4.00, 4.00b, and 4.50 for MS-DOS, in Microsoft Basic Compiler versions 6.00 and 6.00b for MS-DOS and MS OS/2, and in Microsoft Basic PDS versions 7.00 and 7.10 for MS-DOS and MS OS/2, you can directly assign variables of a user-defined TYPE directly to one another if they are of the same TYPE. (LSET can be used for assignment if the record variables differ in TYPE.) The TYPEd variables are assigned in one simple statement, and each and every element of the user-defined TYPE is automatically copied.

Microsoft Basic PDS version 7.00 for MS-DOS and MS OS/2 introduces support for static arrays in user-defined TYPEs. In Basic PDS 7.00 and 7.10, you can directly assign one static array to another by defining the array in a user-defined-TYPE variable and then assigning one variable of this TYPE to another, as shown in Example 1.

You can also write a whole array at once into a disk file, as shown in Example 2.

Code Example 1

The following program can be used in Basic PDS 7.00 and 7.10 to demonstrate the assignment of the contents of one static array to another. (Note that dynamic arrays cannot be placed in user-defined TYPEs.)
   TYPE rec1
     array1(20) AS INTEGER
   END TYPE
   DIM var1 AS rec1, var2 AS rec1
   CLS
   FOR i = 1 TO 20      ' Fill the array in var1:
     var1.array1(i) = i
   NEXT
     var2 = var1          ' Make the assignment.
   FOR i = 1 TO 20      ' Confirm that the array was copied to var2:
     PRINT var2.array1(i)
   NEXT
   END
				

Code Example 2

The following example, compiled in Basic PDS 7.00 or 7.10, shows how to write a whole array to disk at once, using just one PUT# statement:
      TYPE rec1
     array1(20) AS INTEGER
   END TYPE
   DIM var1 AS rec1, var2 AS rec1
   CLS
   FOR i = 1 TO 20      ' Fill the array in var1:
     var1.array1(i) = i
   NEXT

   OPEN "test.dat" FOR RANDOM AS #1
   PUT #1, , var1         ' write whole array to disk all at once.
   CLOSE

   OPEN "test.dat" FOR RANDOM AS #1
   GET #1, , var2      ' Reads array all at once into var2.
   FOR i = 1 TO 20     ' Print the contents of array var2:
     PRINT var2.array1(i);
   NEXT
   CLOSE
				

Modification Type: Minor Last Reviewed: 1/8/2003
Keywords: KB58733