bson_has_field (3) Linux Manual Page
bson_has_field() – Checks to see if key contains an element named key. This also accepts "dotkey" notation such as "a.b.c.d".
Synopsis
bool
bson_has_field (const bson_t *bson,
const char *key);
Parameters
- bson
- A bson_t \&.
- key
- A string containing the name of the field to check for.