EXAMPLE5.C

/*example5.c */ 
/* 
** This example illustrates dbconvert.It converts a 
** number of constants to strings, a number of strings 
** to numerical or binary quantities, and a number of 
** numerical quantities to other numerical types. 
** 
*/ 
 
#if defined(DBNTWIN32) 
#include <windows.h> 
#endif 
 
#include <stdio.h> 
#include <sqlfront.h> 
#include <sqldb.h> 
 
#define ARRAY_LEN20 
 
/* Forward declarations of the error handler and message handler. 
*/ 
int err_handler(DBPROCESS*, int, int, int, char*, char*); 
int msg_handler(DBPROCESS*, DBINT, int, int, char*); 
 
main(argc, argv) 
intargc; 
char*argv[]; 
{ 
/* These variables hold the results of data conversions. */ 
static DBBINARYmy_binary_array[ARRAY_LEN] 
= {0x12, 0x34, 0x56, 0x78, 0x9a, 0xbc, 0xde, 0xf0}; 
DBFLT8my_flt8; 
DBINTmy_int4; 
DBMONEYmy_money; 
DBCHARmy_string[ARRAY_LEN]; 
 
        dbinit();/* initialize dblib */ 
 
/* Install the user-supplied error-handling and message-handling 
* functions. They are defined at the bottom of this source file. 
*/ 
dbmsghandle((DBMSGHANDLE_PROC)msg_handler); 
dberrhandle((DBERRHANDLE_PROC)err_handler); 
 
/* Convert numerical and binary constants to strings. */ 
 
dbconvert 
((DBPROCESS *)NULL, SQLBINARY, my_binary_array, (DBINT)8, 
            SQLCHAR, my_string,(DBINT)-1); 
printf("Binary constant 0x123456789abcdef0 converted to string"); 
printf("\"%s\".\n\n", my_string); 
 
my_flt8 = 55.555; 
dbconvert 
((DBPROCESS *)NULL, SQLFLT8, (BYTE *) &my_flt8, 
            (DBINT)-1, SQLCHAR, my_string, (DBINT)-1); 
printf 
("Floating-pt constant 55.555 converted to string \"%s\".\n\n", 
my_string); 
 
/* Convert string constants to numerical and binary quantities. */ 
 
dbconvert 
((DBPROCESS *)NULL, SQLCHAR, "123", (DBINT)-1, SQLINT4, (BYTE *) 
&my_int4, (DBINT)-1); 
printf 
("String constant \"123\" converted to 4-byte integer %ld.\n\n", 
my_int4); 
 
dbconvert 
((DBPROCESS *)NULL, 
SQLCHAR, "0xfedc", (DBINT)-1, SQLBINARY, my_binary_array, 
            (DBINT)ARRAY_LEN); 
printf("String constant \"0xfedc\" converted to binary sequence "); 
printf("%hx.\n\n", *((DBSMALLINT *)my_binary_array)); 
 
dbconvert 
((DBPROCESS *)NULL, SQLCHAR, "123.456", (DBINT)-1, SQLFLT8, 
   (BYTE *) &my_flt8, (DBINT)-1); 
printf("String constant \"123.456\" converted to "); 
printf("floating-pt number %f.\n\n", my_flt8); 
 
/* Convert numerical types to other numerical types. */ 
 
my_flt8 = 98.76; 
dbconvert 
   ((DBPROCESS *)NULL, SQLFLT8, (BYTE *) &my_flt8, (DBINT)-1, SQLMONEY, 
(BYTE *) &my_money, (DBINT)-1); 
dbconvert 
   ((DBPROCESS *)NULL, SQLMONEY, (BYTE *) &my_money, (DBINT)-1, SQLCHAR, 
       my_string, (DBINT)-1); 
printf 
("floating-pt number %f converted to money value %s.\n\n", 
my_flt8, my_string); 
 
dbconvert 
   ((DBPROCESS *)NULL, SQLMONEY, (BYTE *) &my_money, (DBINT)-1, SQLFLT8, 
       (BYTE *) &my_flt8, (DBINT)-1); 
printf 
("money value %s converted to floating-pt value %f.\n\n", 
my_string, my_flt8); 
 
return(STDEXIT); 
} 
 
int err_handler(dbproc, severity, dberr, oserr, dberrstr, oserrstr) 
DBPROCESS*dbproc; 
intseverity; 
intdberr; 
intoserr; 
char*dberrstr; 
char*oserrstr; 
{ 
    printf("DB-LIBRARY error:\n\t%s\n", dberrstr); 
 
if (oserr != DBNOERR) 
printf("Operating-system error:\n\t%s\n", oserrstr); 
 
if ((dbproc == NULL) || (DBDEAD(dbproc))) 
return(INT_EXIT); 
 
return(INT_CANCEL); 
} 
 
int msg_handler(dbproc, msgno, msgstate, severity, msgtext) 
DBPROCESS*dbproc; 
DBINTmsgno; 
intmsgstate; 
intseverity; 
char*msgtext; 
{ 
printf 
("SQL Server message %ld, state %d, severity %d:\n\t%s\n", 
msgno, msgstate, severity, msgtext); 
return(0); 
}