dbmfirstkey
(PHP 4)
dbmfirstkey — Retrieves the first key from a DBM database
说明
string dbmfirstkey
( resource $dbm_identifier
)
Returns the first key in the database. Note that no particular order is guaranteed since the database may be built using a hash-table, which doesn't guarantee any ordering.
返回值
如果成功则返回 TRUE,失败则返回 FALSE。