AllIsInvisibleCharacter return true if str is full of space.

CheckContent return ture if the content has.

CheckEmail return ture if the email is valid or false if invalid.

CheckPassword return ture if the password is valid or false if invalid.

CheckPhoneNumber return ture if the phoneNumber is valid or false if invalid.

CheckUsername return ture if the username is valid or false if invalid.

CloseDB close the connection of db.

DB return the pointer of db.

DeletePreAndSufSpace delete the space before and after str.

GetHTMLText ...

GetRedis return the pointer of db.

IsBlank return true if str has not validate character.

MarkdownToHTML ...

MaxInt return max(a,b).

MaxInt64 return max(a,b).

MinInt return min(a,b).

MinInt64 return min(a,b).

NowTimestamp return timestamp of now.

OpenDB create a connection of db.

OpenRedis create a connection of redis.

RandomAvatarURL return random profile photo url str to md5 thanks to https://robohash.org.

SubString ...

Timestamp return timestamp of t.