BSON Document Iterator

SYNOPSIS

#include <bson/bson.h>
#define BSON_ITER_HOLDS_DOUBLE(iter) /* ... */
#define BSON_ITER_HOLDS_UTF8(iter) /* ... */
#define BSON_ITER_HOLDS_DOCUMENT(iter) /* ... */
#define BSON_ITER_HOLDS_ARRAY(iter) /* ... */
#define BSON_ITER_HOLDS_BINARY(iter) /* ... */
#define BSON_ITER_HOLDS_UNDEFINED(iter) /* ... */
#define BSON_ITER_HOLDS_OID(iter) /* ... */
#define BSON_ITER_HOLDS_BOOL(iter) /* ... */
#define BSON_ITER_HOLDS_DATE_TIME(iter) /* ... */
#define BSON_ITER_HOLDS_NULL(iter) /* ... */
#define BSON_ITER_HOLDS_REGEX(iter) /* ... */
#define BSON_ITER_HOLDS_DBPOINTER(iter) /* ... */
#define BSON_ITER_HOLDS_CODE(iter) /* ... */
#define BSON_ITER_HOLDS_SYMBOL(iter) /* ... */
#define BSON_ITER_HOLDS_CODEWSCOPE(iter) /* ... */
#define BSON_ITER_HOLDS_INT32(iter) /* ... */
#define BSON_ITER_HOLDS_TIMESTAMP(iter) /* ... */
#define BSON_ITER_HOLDS_INT64(iter) /* ... */
#define BSON_ITER_HOLDS_DECIMAL128(iter) /* ... */
#define BSON_ITER_HOLDS_MAXKEY(iter) /* ... */
#define BSON_ITER_HOLDS_MINKEY(iter) /* ... */
#define BSON_ITER_HOLDS_INT(iter) \


   (BSON_ITER_HOLDS_INT32 (iter) || BSON_ITER_HOLDS_INT64 (iter))
#define BSON_ITER_HOLDS_NUMBER(iter) \


   (BSON_ITER_HOLDS_INT (iter) || BSON_ITER_HOLDS_DOUBLE (iter))
#define BSON_ITER_IS_KEY(iter, key) \


   (0 == strcmp ((key), bson_iter_key ((iter))))
typedef struct {


   /*< private >*/
} bson_iter_t;

DESCRIPTION

bson_iter_t is a structure used to iterate through the elements of a bson_t. It is meant to be used on the stack and can be discarded at any time as it contains no external allocation. The contents of the structure should be considered private and may change between releases, however the structure size will not change.

The bson_t MUST be valid for the lifetime of the iter and it is an error to modify the bson_t while using the iter.

EXAMPLES

bson_iter_t iter;
if (bson_iter_init (&iter, my_bson_doc)) {


   while (bson_iter_next (&iter)) {


      printf ("Found a field named: %s\n", bson_iter_key (&iter));


   }
}

bson_iter_t iter;
if (bson_iter_init (&iter, my_bson_doc) && bson_iter_find (&iter, "my_field")) {


   printf ("Found the field named: %s\n", bson_iter_key (&iter));
}

bson_iter_t iter;
bson_iter_t sub_iter;
if (bson_iter_init_find (&iter, my_bson_doc, "mysubdoc") &&


    (BSON_ITER_HOLDS_DOCUMENT (&iter) || BSON_ITER_HOLDS_ARRAY (&iter)) &&


    bson_iter_recurse (&iter, &sub_iter)) {


   while (bson_iter_next (&sub_iter)) {


      printf ("Found key \"%s\" in sub document.\n", bson_iter_key (&sub_iter));


   }
}

bson_iter_t iter;
if (bson_iter_init (&iter, my_doc) &&


    bson_iter_find_descendant (&iter, "a.b.c.d", &sub_iter)) {


   printf ("The type of a.b.c.d is: %d\n", (int) bson_iter_type (&sub_iter));
}

AUTHOR

MongoDB, Inc

COPYRIGHT

2009-present, MongoDB, Inc.