Important Notice

The pages on this site contain documentation for very old MS-DOS software, purely for historical purposes. If you're looking for up-to-date documentation, particularly for programming, you should not rely on the information found here, as it will be woefully out of date.

                                                 ◄Contents►  ◄Index►  ◄Back►
─────────────────────────────────────────────────────────────────────────────
                           ◄Knowledge Base Contents►  ◄Knowledge Base Index►
 
 Passing a Basic Array of User-Defined Type to C - Q27302
 
 The following example demonstrates how to pass an array of
 user-defined-type records from compiled Basic to Microsoft C.
 
 This information applies to the Standard and Professional Editions of
 Microsoft Visual Basic version 1.0 for MS-DOS and to Microsoft C
 Compiler version 7.0.
 
 To compile this example in Visual Basic for MS-DOS, execute the
 following commands:
 
    BC BMODULE.BAS;
    CL -c -AM CMODULE.C
    LINK BMODULE.OBJ CMODULE.OBJ;
 
 Basic Program
 -------------
 
 TYPE record
    a AS INTEGER
    b AS STRING * 20
    c AS SINGLE
 END TYPE
 
 DECLARE SUB TypeArray CDECL (_
             BYVAL p1o AS INTEGER,_
             BYVAL p1s AS INTEGER)
 
 DIM element(10) AS record
 
 CLS
 
 FOR I = 0 TO 10
    element(I).a = 128 + I
    element(I).b = STR$(I) + ". " + DATE$ + CHR$(0)
    element(I).c = 39.6 * I
 NEXT I
 
 CALL TypeArray(VARPTR(element(0)), VARSEG(element(0)))
 END
 
 C Routine
 ---------
 
 #include <stdio.h>
 
 struct record {
    int a;
    char b[20];
    float c;
 };
 
 void TypeArray(struct record far *element) {
    int i;
 
    for (i=0; i<3; i++) {
       printf("Record[%d].A = %d\",  i, element->a);
       printf("Record[%d].B = %Fs\", i, element->b);
       printf("Record[%d].C = %f\",  i, element->c);
       printf("\");
       element++;
    }
  }
 
 Output
 ------
 
 Record[0].A = 128
 Record[0].B =  0. 02-02-1988
 Record[0].C = 0.000000
 
 Record[1].A = 129
 Record[1].B =  1. 02-02-1988
 Record[1].C = 39.599998
 
 Record[2].A = 130
 Record[2].B =  2. 02-02-1988
 Record[2].C = 79.199997