php --ri [扩展名称]
例如：
php --ri mongodb mongodb MongoDB support => enabled MongoDB extension version => 1.5.4 MongoDB extension stability => stable libbson bundled version => 1.13.0 libmongoc bundled version => 1.13.0 libmongoc SSL => enabled libmongoc SSL library => Secure Transport libmongoc crypto => enabled libmongoc crypto library => Common Crypto libmongoc crypto system profile => disabled libmongoc SASL => enabled libmongoc ICU => disabled libmongoc compression => enabled libmongoc compression snappy => disabled libmongoc compression zlib => enabled Directive => Local Value => Master Value mongodb.debug => no value => no value